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					TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL



                                           DIVISION 23 – MECHANICAL


23.01    GENERAL

         The Tarrant County College District (TCCD) Facilities Board (FB) or its representative(s) will
         review design work to the extent necessary to assure compliance with TCCD Design Standards
         and applicable codes. The FB will not undertake a detailed technical review of your work. The FB
         must approve any deviations from the TCCD Design Standards.
         As a design professional it is your responsibility to ensure code compliance, completeness, and
         correctness of the design, cost estimate, and all engineering concepts and details of the work.
         This responsibility includes the coordination of the various architectural, civil, structural,
         mechanical, electrical, and other subdivisions with each other and with the specifications.
         You should expect a more thorough review than that given by a ‘typical’ client. Even so, the FB's
         review, approval or acceptance of, and payment for the design services cannot be construed as a
         waiver of any rights under the design agreement.
         If the FB determines that a design submittal is unacceptable, a re-submittal will be required.
         Before re-submittal, your representative(s) will meet with the FB or its representative(s), at no
         additional cost to TCCD, to resolve any issue(s) with the design.
         During the construction phase of the project the FB or their representative(s) will review all project
         submittals; again you should expect a more thorough review than that given by a ‘typical’ client.
         If the FB determines that a submittal, or a portion of a submittal, is unacceptable, a re-submittal
         will be required. Before re-submittal, your representative(s) will meet with the FB or its
         representative(s), at no additional cost to TCCD, to resolve any issue(s) with the submittal.

23.02    INTRODUCTION

         23.02.1          The design standards contained herein are intended to assist the engineer in
                          developing a system design adhering to the level of quality, efficiency, and system
                          operability consistent with the expectations of TCCD. The Design Professional shall
                          communicate with the FB for specific requirements that may not be expressly stated
                          within this document. Existing systems vary from site to site and even within the
                          same building.
         23.02.2          The systems that are referenced in this chapter or would normally be referenced in
                          this chapter in specifications shall be designed with sustainability, the highest energy
                          efficiency, utilize energy recovery techniques, the best Life Cycle Costs and support
                          the initiatives of TCCD’s Sustainable Resource Management Plan. TCCD is under a
                          Texas legislative mandate, HB-3693 to reduce energy consumption 5 % a year for six
                          (6) years.

23.03    REFERENCES/CODES

         23.03.1          AABC - National Standards for Field Measurement and Instrumentation, Total
                          System Balance.
         23.03.2          ABMA 9 - Load Ratings and Fatigue Life for Ball Bearings.
         23.03.3          ABMA 11 - Load Ratings and Fatigue Life for Roller Bearings.
         23.03.4          AMCA 99 - Standards Handbook.
         23.03.5          AMCA 210 - Laboratory Methods of Testing Fans for Rating Purposes.
         23.03.6          AMCA 300 - Test Code for Sound Rating Air Moving Devices.

Issued January 31, 2009                                                                             23 00 00 1/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


         23.03.7          AMCA 301 - Method of Calculating Fan Sound Ratings from Laboratory Test Data.
         23.03.8          AMCA 500 - Test Method for Louvers, Dampers and Shutters.
         23.03.9          ASHRAE 15 - Safety Code for Mechanical Refrigeration.
         23.03.10         ASHRAE 52 - Method of Testing Air Cleaning Devices used in General Ventilation for
                          Removing Particulate Matter.
         23.03.11         ASHRAE 62 - Ventilation For Acceptable Indoor Air Quality.
         23.03.12         ASHRAE 90.1 - Energy Standard for Buildings.
         23.03.13         ASHRAE - Handbook 1993 Fundamentals; Chapter 32 - Duct Design.
         23.03.14         ASHRAE - Handbook 1992 HVAC Systems and Equipment; Chapter 16 - Duct
                          Construction.
         23.03.15         ASHRAE - 1984 Systems Handbook: Chapter 37, Testing, Adjusting and Balancing.
         23.03.16         ASHRAE - Applications Handbook: Sound and Vibration Control.
         23.03.17         AGA - Directory of Certified Appliances and Accessories.
         23.03.18         AGA Z21.22 - Relief Valves and Automatic Gas Shutoff Devices for Hot Water
                          Supply Systems.
         23.03.19         AGA Z21.13 - Gas-Fired Low-Pressure Steam and Hot Water Boilers.
         23.03.20         ANSI A13.1 - Scheme for the Identification of Piping Systems.
         23.03.21         ANSI/IEEE C2 - National Electrical Safety Code.
         23.03.22         ANSI S12.60 - Classroom Acoustics
         23.03.23         ARI 550 - Centrifugal or Rotary Water - Chilling Packages.
         23.03.24         ARI 650 - Air Outlets and Inlets.
         23.03.25         ASME A112.26.1M - Water Hammer Arresters.
         23.03.26         ASME B16.18 - Cast Copper Alloy Solder Joint Pressure Fittings.
         23.03.27         ASME B16.23 - Cast Copper Alloy Solder Joint Drainage Fittings – DMV.
         23.03.28         ASME B16.29 - Wrought Copper and Wrought Copper Alloy Solder Joint Drainage
                          Fittings – DWV.
         23.03.29         ASME B31.9 - Building Services Piping.
         23.03.30         ASME SEC I - Boiler and Pressure Vessels Code - Rules for Construction of Power
                          Boilers.
         23.03.31         ASME SEC IV - Boiler and Pressure Vessels Code - Rules for Construction of
                          Heating Boilers.
         23.03.32         ASME SEC VIII - Boilers and Pressure Vessels Code - Rules for Construction of
                          Pressure Vessels.
         23.03.33         ASSE 1011 - Hose Connection Vacuum Breakers.
         23.03.34         ASSE 1013 - Backflow Preventers, Reduced Pressure Principle.
         23.03.35         ASSE 1019 - Wall Hydrants, Frost-Proof Automatic Draining Anti-Backflow Types.
         23.03.36         ASTM A 47 - Ferritic Malleable Iron Castings.
         23.03.37         ASTM A 53 - Pipe, Steel, Black and Hot-Dipped Zinc Coated, Welded and Seamless.
         23.03.38         ASTM A 74 - Cast Iron Soil Pipe and Fittings.


Issued January 31, 2009                                                                        23 00 00 2/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


         23.03.39         ASTM A 234 - Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate
                          and Elevated Temperatures.
         23.03.40         ASTM A 527 - Steel Sheet, Zinc-Coated (Galvanized) by Hot-Dip Process, Lock
                          Forming Quality.
         23.03.41         ASTM B 32 - Solder Metal.
         23.03.42         ASTM B 88 - Seamless Copper Water Tube.
         23.03.43         ASTM B 306 - Copper Drainage Tube (DWV).
         23.03.44         ASTM C 195 - Mineral Fiber Thermal Insulation Cement.
         23.03.45         ASTM C 533 - Calcium Silicate Block and Pipe Thermal Insulation.
         23.03.46         ASTM C 547 - Mineral Fiber Preformed Pipe Insulation.
         23.03.47         ASTM C 552 - Cellular Glass Block and Pipe Thermal Insulation.
         23.03.48         ASTM C 553 - Mineral Fiber Blanket and Felt Insulation.
         23.03.49         ASTM C 612 - Mineral Fiber Block and Board Thermal Insulation.
         23.03.50         ASTM C 1126 - Rigid Cellular Phenolic Thermal Insulation.
         23.03.51         ASTM D 3034 - Type PSM Polyvinyl Chloride) (PVC) Sewer Pipe and Fittings (4
                          inches to 15 inches).
         23.03.52         ASTM E 84 - Surface Burning Characteristics of Building Materials.
         23.03.53         ASTM E 96 - Water Vapor Transmission of Materials.
         23.03.54         ASTM E 917 - Measuring Life-Cycle Costs of Buildings and Systems.
         23.03.55         AWS - Welding and Brazing Qualifications.
         23.03.56         AWS A5.8 - Brazing Filler Metal.
         23.03.57         AWS D1.1 - Structural Welding Code.
         23.03.58         AWWA C151 - Ductile-Iron Pipe, Centrifugally Cast, for Water or Other Liquids.
         23.03.59         AWWA D100 - Standard for Welded Steel Tanks for Water Storage.
         23.03.60         CISPI 301 - Cast Iron Soil Pipe and Fittings for Hubless Cast Iron Sanitary Systems.
         23.03.61         CISPI 310 - Coupling for Use in Connection with Hubless Cast Iron Soil Pipe and
                          Fittings for Sanitary and Storm Drain, Waste, and Vent Piping Applications.
         23.03.62         CTI ATC-105 - Acceptance Test Code for Water Cooling Towers.
         23.03.63         CTI STD-201 - Certification of Water Cooling Tower Thermal Performance.
         23.03.64         ISA Standard S5.1 - Instrumentation Symbols and Identification.
         23.03.65         NEMA 250 - Enclosures for Electrical Equipment (1000 Volts Maximum).
         23.03.66         NFPA 30 - Flammable and Combustible Liquids.
         23.03.67         NFPA 31 - Installation of Oil Burning Equipment.
         23.03.68         NFPA 54 - National Fuel Gas Code.
         23.03.69         NFPA 70 - National Electrical Code.
         23.03.70         NFPA 90A - Installation of Air Conditioning and Ventilating Systems.
         23.03.71         NFPA 90B - Installation of Warm Air Heating and Air Conditioning Systems.
         23.03.72         NFPA 211 - Chimneys, Fireplaces, Vents, and Solid Fuel Burning Appliances.


Issued January 31, 2009                                                                           23 00 00 3/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


         23.03.73         PDI WH-201 - Water Hammer Arresters.
         23.03.74         SMACNA 1035 - HVAC Duct Construction Standards - Metal and Flexible.
         23.03.75         UL 33 - Heat Responsive Links for Fire-Protection Service.
         23.03.76         UL 103 - Factory-built Chimneys for Residential Type and Building Heating
                          Appliances.
         23.03.77         UL 181 - Factory-Made Air Ducts and Air Connectors.
         23.03.78         UL 441 - Gas Vents.
         23.03.79         UL 465 - Central Cooling Air Conditioners.
         23.03.80         UL 555 - Fire Dampers.
         23.03.81         UL 555S - Safety Leakage Rated Dampers for Use in Smoke Control Systems.
         23.03.82         UL 726 - Oil-Fired Boiler Assemblies.
         23.03.83         US DOE FEMP - NIST Handbook 135, Life Cycle Costing Manual for the Federal
                          Energy Management Program.
         23.03.84         USGBC LEED-NC (Leadership in Energy and Environmental Design) Green Building
                          Rating System Reference Guide 2.2 for New Construction and Major Renovations.
         23.03.85         USGBC LEED-EB (Leadership in Energy and Environmental Design) Green Building
                          Rating System Reference Guide 2.0 for Existing Buildings.
         23.03.86         Refer to section 2.0 CODES & STANDARDS for a list of additional applicable codes
                          and standards.

23.04    GENERAL REQUIREMENTS

         23.04.1          Provide a list of symbols and abbreviations used on drawings. Conform to TCCD
                          CAD and symbol standards.
         23.04.2          List scheduled mechanical equipment on the drawings.
         23.04.3          Do not locate mechanical, plumbing or other piping in transformer vaults, elevator
                          hoist-ways, elevator equipment rooms, or telecommunications equipment rooms.
         23.04.4          Contractor to furnish and install meters for natural gas, domestic water, domestic hot
                          water, chilled water and heating hot water service energy for each individual building.
                          Provide isolation valves to accommodate meter service. These meters shall tie into
                          the BAS. The chilled water and hot water service energy may be calculated values
                          derived from flow and temperature differential sensors. The Design Professional shall
                          coordinate with the FB for specific requirements. Each building will be taken on a
                          case by case basis.
         23.04.5          Verify location, capacity and connection of new building services to existing utilities
                          (chilled water, heating hot water, domestic water, sanitary sewer, natural gas, etc)
                          with the FB.
         23.04.6          Design connections for hydronic heating and cooling coils to be piped in a
                          counterflow arrangement.
         23.04.7          Coordinate openings in existing roofs with the Design Professional (DP) to avoid
                          nullifying the roof warranty and with the TCCD Project Manager (PM) to assure
                          compliance with the Roof Management Plan.
         23.04.8          Provide sufficient unions and flanges to permit removal of equipment.
         23.04.9          Provide a dielectric union or dielectric nipples with a non-dielectric union to join
                          dissimilar piping materials.

Issued January 31, 2009                                                                            23 00 00 4/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


         23.04.10         Provide adequate space to permit service for valves and related piping specialties.
                          Layout equipment with sufficient service clearances to ensure proper maintenance.
                          Install equipment so that tube pull, filter replacement, strainer cleaning, equipment
                          draining, air handler coil pull, motor and shaft replacement and other maintenance
                          service can be accommodated. Locate equipment like VAV terminal units in corridors
                          and common areas if at all possible to minimize noise and service disruption to
                          classrooms, meeting rooms, etc. Indicate required clearances by using dashed lines
                          on the Drawings. Clearances shall not be less than manufacturer’s
                          recommendations.
         23.04.11         Group piping, valves and accessories in common locations to accommodate service
                          and maintenance. Design and arrange systems requiring regular preventative
                          maintenance for ease of access and maximum serviceability.
         23.04.12         Slope piping systems to permit drainage. Provide drain valves at low points and
                          automatic air vents at high points. Use eccentric reducers to maintain top of pipe
                          level.
         23.04.13         Conceal piping within the building inside walls, above ceilings or in furred chases.
                          Use exposed piping only in mechanical rooms unless directed otherwise.
         23.04.14         Provide a minimum two (2) inch clearance between insulated piping and other piping,
                          structural members or obstructions.
         23.04.15         Provide one piece (preferred) or split hinge polished stainless steel escutcheons for
                          piping entering floors, walls, and ceilings in exposed spaces. Secure plates in place
                          by internal spring tension or set screws.
         23.04.16         Isolate domestic water lines for building services from cross connection by means of
                          a code-approved backflow preventer. Provide additional backflow protection devices
                          in process water connections off the building main service. Coordinate with the FB to
                          obtain flow test data to ensure adequate flow and pressure exists to support building
                          and systems. Avoid installing backflow preventers in series arrangement.
         23.04.17         Avoid routing chilled, hot water and domestic water piping directly beneath floor
                          slabs. Routing of pipes beneath floor slabs must be approved by the FB and Design
                          Professionals.
         23.04.18         The Design Professionals shall be responsible for preparation and follow-up
                          correspondence with the Texas Commission on Environmental Quality (TCEQ) for
                          any necessary permits associated with adhering to environmental emissions
                          requirements.
         23.04.19         Avoid the use of domestic water as a process-cooling source for laboratory or other
                          equipment.
         23.04.20         Allowed refrigerants: HCFC-123, HFC-134a, and HFC-410A.
         23.04.21         Provide three-phase power for motors 3/4-horsepower and larger.
         23.04.22         Tee-pulling of copper tube is not allowed.
         23.04.23         Grooved end piping with mechanical couplings is not allowed in mechanical or
                          plumbing piping systems. It will only be considered on a case by case basis by the
                          FB.
         23.04.24         Provide valves located more than seven (7) feet from floor in mechanical room areas
                          with chain operated sheaves. Extend chains to five (5) feet above floor and hook to
                          clips arranged to clear walking aisles.
         23.04.25         Provide major mechanical equipment, including chillers, boilers and cooling towers,
                          with minimum five (5) year warranty and five (5) year service contract with options for



Issued January 31, 2009                                                                            23 00 00 5/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          ten (10) year warranty and ten (10) year service contract. Coordinate with the FB on
                          details and approvals for additional service cost allowances.
         23.04.26         Perform complete energy simulation calculations to model building heating, cooling,
                          lighting, ventilating, and other energy flows at end of Design Development.
                          Calculations shall comply with ASHRAE 90.1-2004, and the IECC, using Trane Trace
                          700 or DOE2 software. Simulation calculations shall be used for load estimating,
                          equipment sizing and selection and optimization of complete system for Life Cycle
                          Cost Analysis (LCCA). The results of the analysis, including all data files for Trane
                          Trace 700 or DOE2, shall be presented in usable format and coordinated with the FB.
         23.04.27         Coordinate mechanical system design requirements with overall project design
                          objectives with respect to LEED requirements, specific environmental performance
                          objectives etc., as identified by the FB.
         23.04.28         Upon design completion, provide the FB with a report package in hard copy and
                          electronic format containing a narrative description of the mechanical system design,
                          completed energy simulation calculations, ASHRAE 90.1 and IECC compliance
                          forms, a detailed narrative of control system sequence of operations, and the LCCA.

23.05    DESIGN CONDITIONS

         23.05.1          Use the general guidelines listed in Table 23.05.1-A for indoor and outdoor design
                          conditions and equipment selection purposes; IECC may override TCCD preferred
                          parameters:

                          TABLE 23.05.1-A – INDOOR AND OUTDOOR DESIGN CONDITIONS

                           SUMMER OUTDOOR                   105ºF dry bulb / 80ºF wet bulb
                           DESIGN:

                           WINTER OUTDOOR DESIGN:           0ºF (extreme minimum design)

                           DEGREE DAYS:                     HDD65: 2,304
                                                            CDD50: 6,557
                           INDOOR DESIGN;                   71ºF dry bulb / 55% maximum RH (summer)
                           OCCUPIED AREAS*:                 72ºF dry bulb (winter)

                           UNOCCUPIED AREAS:                   Design for 80ºF (summer) and 60ºF (winter) in mechanical
                                                               and electrical rooms, and other non-occupied areas.
                          *Note: Special use areas such as telecom areas, laboratories, shops, etc. may have specific
                          design criteria outside the ranges listed above. Design in accordance with project-specific
                          requirements.

         23.05.2          Provide the required ventilation air for building areas in accordance with ASHRAE 62
                          (latest edition), Ventilation for Acceptable Air Quality.
         23.05.3          Provide dedicated outside air handling units sized to pre-treat the outside air supply
                          for delivery to the intake of the building/zone air handling unit intake. The units shall
                          be energy recovery (ER) type units utilizing energy wheels, air-to-air heat
                          exchangers, runaround loops, etc. Evaluate using an LCCA to support additional
                          costs while maximizing energy savings and minimizing peak demand. Outside air
                          units need to be sized to supply air dry enough to offset latent loads in the spaces.
                          Utilize Demand Controlled Ventilation techniques to control outside air ventilation
                          rates utilizing CO2 sensors and occupancy sensors.
         23.05.4          Locate building discharge air openings to avoid entraining potentially contaminated
                          air into the building ventilation system. Locate air intakes to avoid introducing air
                          pollutants into the building, a minimum of 15’-0” above grade, with sufficient

Issued January 31, 2009                                                                                 23 00 00 6/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          separation to avoid recirculation of the air discharged from nearby equipment,
                          including but not limited to cooling towers, boiler flues, chemical fume hoods, general
                          exhaust, etc. Roof mounted outside air intakes shall be required if at all possible on
                          existing facilities. Detailed computational fluid dynamics simulations may be required
                          depending upon nearby potential contaminant sources.
         23.05.5          Zone mechanical systems in accordance with sound engineering judgment relating to
                          varying load and envelope conditions, function of space, occupancy schedules, etc.
                          Coordinate system zoning with the FB during the conceptual design stage. Provide
                          individual zone control for each auditorium, classroom, conference room, and special
                          use type room. Groups of offices may be grouped into zones, with no more than two
                          (2) offices per zone.
         23.05.6          Utilize SMACNA IAQ Guidelines for Occupied Buildings under Construction during
                          the construction and pre-occupancy phases of a project.
         23.05.7          Document maximum allowable and design noise levels for building classrooms,
                          offices or other acoustically sensitive areas. Design such spaces in accordance with
                          ASHRAE Handbook-Applications as the maximum or specifications from acoustic
                          consultant for lower sound level recommendations.
         23.05.8          Refer to Table 23.05.8 for general pressure relationships and ventilation
                          requirements for certain areas.


                 TABLE 23.05.8 – PRESSURE RELATIONSHIPS AND VENTILATION REQUIREMENTS

                                           PRESSURE                                  ALL AIR
                                          RELATIONSHIP             MINUMUM         EXHAUSTED
                         AREA             TO ADJACENT           OUTDOOR AIR              TO        RECIRCULATION
                    DESCRIPTION              AREAS*            REQUIREMENTS        OUTDOORS           PERMITTED
                  Auditoriums                    P                   Note 1              No               Yes
                  Classrooms                     P                   Note 1              No               Yes
                  Computer Rooms                 P                   Note 1              No               Yes
                  Copy Centers                   N                   Note 1             Yes                No
                  Darkrooms                      N                   Note 1             Yes                No
                  Dining Areas                   P                   Note 1              No               Yes
                  Janitors Closets               N                   Note 3             Yes                No
                  Kitchens                       N                   Note 1             Yes                No
                  Laboratories                 Note 4                Note 4            Note 4            Note 4
                  Laundry                        N                   Note 1             Yes                No
                  Libraries                      P                   Note 1              No               Yes
                  Locker Areas                   N                   Note 1              No               Yes
                  Lounges                        N                   Note 1              No               Yes
                  Mech/Elec Rooms              Note 2                Note 1             Yes                No
                  Offices                        P                   Note 1              No               Yes
                  Telecom Rooms                  P                   Note 1              No               Yes
                  Restrooms                      N                   Note 3             Yes                No
                 *Legend: P = Positive, N = Negative
                 Notes:
                 1.    Provide ventilation air for all building areas in accordance with ASHRAE 62 - Ventilation For
                       Acceptable Air Quality (Latest Edition) Requirements.
                 2.    Mechanical rooms with gas-fired equipment must be maintained positive; otherwise negative
                       pressurization is acceptable.
                 3.    Transfer from corridors permitted. Exhaust air quantity shall be greater of 1.0 cfm/ft2 (Janitor
                       Closets) or 2.0 cfm/ft2 (Restrooms) or as required by ASHRAE STANDARD 62 - Ventilation
                       For Acceptable Air Quality (Latest Edition).
                 4.    Discuss specific requirements with the project manager. Requirements may vary.



Issued January 31, 2009                                                                                 23 00 00 7/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


23.06    MECHANICAL ROOMS

         23.06.1          GENERAL REQUIREMENTS
                          A.   Design mechanical rooms to provide adequate maintenance clearances for
                               equipment per code requirements and manufacturer’s recommendations (i.e.,
                               tube and coil pull spaces, compressor removal spacing, fan and fan shaft,
                               motor, filter service, etc.). Provide adequate means of access for the
                               replacement of the largest piece of equipment within a room. Show required
                               service clearances using dashed lines on the Drawings.
                          B.   Provide mechanical rooms with an automatic ventilation system.
                          C.   Provide mechanical rooms with a minimum of one (1) floor drain and hose bib.
                          D.   Pipe equipment drains, condensate, blow-down lines, etc. to a floor drain with a
                               code-approved air gap fitting.
                          E.   The Design Professional shall coordinate with the FB to locate mechanical
                               rooms to provide direct access from the building exterior if practical. Avoid
                               locating mechanical rooms in areas where vibration and/or noise would be
                               objectionable.
                          F.   Design mechanical rooms containing chillers or other refrigerant containing
                               equipment to comply with the requirements of ASHRAE 15 (latest version) as
                               applicable.
                          G.   Design mechanical rooms to accommodate space for additional equipment
                               (chillers, boilers, pumps, air handlers, etc.) as required to support future planned
                               campus growth. Coordinate with the FB for requirements.

23.07    CAMPUS UTILITIES

         23.07.1          GENERAL REQUIREMENTS
                          A.   Coordinate new building and expansion projects with the FB to ensure new and
                               revised loads are accounted for in central plant equipment capacities.
                          B.   Design piping utilities serving more than one building to be fully accessible for
                               maintenance. Avoid routing piping beneath buildings unless accessible for
                               service and maintenance.
                          C.   Coordinate design to maintain utility services to all buildings during design
                               and/or renovation activities.
                          D.   Control chilled and heating hot water services for separate buildings using
                               individual two-way pressure-independent flow control valves (Belimo or Flow
                               Control Industries Delta-P valve) with ports on the return side of air handling and
                               terminal unit coil piping. Modulate valve position based on maintaining either the
                               space temperature, coil deck temperature or the highest delta degrees
                               Fahrenheit (0F) for the central plant chilled and heating hot water. Provide
                               automatic valve control override if required space temperature controls are out
                               of range.
                          E.   Provide each building with two (2) tertiary pumps each for the chilled and
                               heating hot water systems, piped in parallel, each sized for 60% of the design
                               flow rate. Provide appropriately sized low head loss bypass with check valve
                               around pumps to support primary and/or secondary campus pumping if not
                               available on existing campuses. Provide each pump with a variable frequency
                               drive controlled off building loop pressure differential requirements. If there is
                               sufficient primary or secondary loop head to provide the needed flows, then this


Issued January 31, 2009                                                                              23 00 00 8/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               part of the system is not required. The Design Professional shall coordinate this
                               section with the FB.
                          F.   Size internal building chilled water and heating hot water distribution piping
                               downstream of tertiary pumps to maintain water velocity less than four (4) feet
                               per second and less than three (3) feet of pressure loss per 100 feet of pipe.
                               Size building services piping for 125% of the expected design system flow rate.
                               Use two-way pressure independent control valves for building air handler coil
                               control.
                          G.   Individually meter system makeup water services and report makeup rate and
                               totalized flow to Building Automation System (BAS). The Design Professional
                               shall coordinate this section with the FB.
                          H.   Provide expansion loops, offsets, anchors, and guides as required to
                               accommodate pipe thermal expansion in accordance with ASHRAE
                               recommendations.
         23.07.2          CENTRAL UTILITY PLANT AND CAMPUS DISTRIBUTION SYSTEMS
                          A.   A central utility plant, housing chillers, boilers, distribution pumps, accessories
                               and controls will be used to provide year round heating and cooling services to
                               the campus buildings and facilities.
                          B.   Design the main campus chilled water system to operate with the highest overall
                               system efficiencies. Variable primary flow central plant designs with parallel
                               multiple pump designs are preferred. Primary-secondary arrangement, with
                               constant speed pumps on the primary loop serving the chiller or chillers (one
                               pump per chiller in a parallel header arrangement for operational flexibility) and
                               multiple secondary pumps equipped with variable frequency drives to control
                               system pressure at the most hydraulically demanding location in the distribution
                               system. Side stream chiller configurations may be utilized in a case by case
                               basis. Design system piping to allow two-way flow through the de-coupler pipe
                               between the primary and secondary loops.
                          C.   Design central plant mechanical equipment, including chillers, boilers, cooling
                               towers and distribution pumps, with N+1 redundancy to accommodate the loss
                               of the largest piece of operating equipment at design conditions.
                          D.   Design the main campus heating hot water system to operate in a primary-
                               secondary arrangement, with constant speed boiler circulating pumps (one
                               pump dedicated per boiler) and multiple secondary pumps equipped with
                               variable frequency drives to control system pressure at the most hydraulically
                               demanding location in the distribution system. Design system piping to allow
                               two-way flow through the de-coupler pipe between the primary and secondary
                               loops.
                          E.   Design new chilled water production system to supply a temperature of 40ºF
                               with a minimum chilled water return temperature of 62ºF. Existing systems may
                               vary from these values. The Design Professional shall coordinate this section
                               with the FB.
                          F.   Design the chilled water distribution system to use a supply temperature of 40ºF
                               with a minimum chilled water return temperature of 62ºF. Existing systems may
                               vary from these values. The Design Professional shall coordinate this section
                               with the FB.
                          G.   The heating hot water system shall be designed using a supply design
                               temperature of 140ºF with a return water temperature of 100ºF. Existing
                               systems may vary from these values. Configure heating hot water system for
                               temperature reset based on outside air temperature through BAS.


Issued January 31, 2009                                                                             23 00 00 9/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          H.   Design main campus chilled and heating hot water distribution piping in a
                               looped arrangement designed to serve all current and planned future buildings.
                               Size distribution mains with pipe velocities not exceeding four (4) feet per
                               second at the expected campus build-out design loads. Maintain uniform pipe
                               sizing throughout the campus distribution system (i.e. avoid the use of reducers
                               or contractions in remote sections of the main distribution system). Utilize
                               multiple loops if feasible, to allow serving campus facilities from redundant flow
                               paths.
                          I.   THERMAL ENERGY STORAGE (TES): Evaluate the application of thermal
                               energy storage in the campus chilled water system with respect to energy
                               efficiency and utility savings based on LCCA, to determine viability. Refer to the
                               Life Cycle Cost Analysis section for additional information.
                               1.   Thermal Energy Storage (TES) to consist of a welded steel cylindrical tank
                                    with integral internal flow distributors designed to store thermally stratified
                                    chilled water. The tank will act as a de-coupler between the primary
                                    (production) and secondary (distribution) systems.
                               2.   The TES system will be fully integrated with chilled water supply system.
                                    The TES system shall store chilled water produced during "off-peak"
                                    periods to partially offset "on-peak" thermal loads.
                               3.   Provide welded steel tank in full compliance with AWWA D300, with fixed
                                    roof, tank fittings, ladder, railing and other elements as required by OSHA,
                                    flow diffuser, tank coatings, instrumentation, tank foundation and
                                    associated earthworks, tank anchorage, exterior tank roofing, roof and wall
                                    insulation, and wall insulation coating.
                               4.   Utilize a life cycle cost approach to determine the optimal TES tank size
                                    and configuration (gallons), capacity (ton-hours) and full storage versus
                                    partial storage operational setup.
         23.07.3          CENTRAL CAMPUS UNDERGROUND UTILITY DISTRIBUTION
                          A.   UTILITY TUNNELS:
                               1.   When layout and topography permit, and when feasible for campus
                                    construction, expansion and renovation projects, provide a walk able
                                    underground utility tunnel extending from the campus central plant. The
                                    utility tunnel shall extend from the central plant and be routed in the most
                                    efficient manner possible to serve the extended campus buildings.
                               2.   Provide branch tunnels extending from the main tunnel to serve individual
                                    buildings or groups of buildings. Isolate building branch piping from main
                                    distribution piping using butterfly valves.
                               3.   Design the utility tunnel to carry main campus distribution systems
                                    including chilled water, heating hot water, domestic cold and hot water,
                                    electrical, voice/data, BAS, etc. Include natural gas and sanitary sewer on
                                    a case by case basis as identified by the FB. Do not route storm sewer
                                    services within utility tunnels.
                               4.   The Design Professionals shall coordinate the tunnel design with the FB.
                                    Minimum tunnel height should be eight (8) feet clear, with a minimum of
                                    five (5) feet clear space between supports or between wall and supports for
                                    walk able access. Design utility tunnels constructed of pre-cast or cast-in-
                                    place concrete in accordance with ACI standards.
                               5.   Provide inserts and plates embedded in the tunnel walls for piping, wiring
                                    and cable tray supports.
                               6.   Slope tunnel floors towards the piping side of the tunnel to minimize water
                                    on walking surfaces, and provide drain piping beneath tunnel floor.


Issued January 31, 2009                                                                              23 00 00 10/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               7.    Provide provisions for tunnel extensions to serve planned future buildings.
                               8.    Provide permanent tunnel lighting at manholes and spaced uniformly
                                     throughout length of tunnel to allow safe access and maintenance. Provide
                                     service receptacles spaced throughout the tunnel for maintenance
                                     activities.
                               9.    Maintain a uniform tunnel slope between access manholes. Provide
                                     manhole sections for tunnel access. Below the top manhole section,
                                     provide steel grated landings connected by a ship ladder and safety railing.
                                     Provide galvanized ladders with safety cages for tunnel access through the
                                     top grating. Avoid locating manholes in roadways.
                               10.   Provide for drainage of storm water through manhole using offset opening
                                     to prevent rainwater from entering the tunnel.
                               11.   Provide a permanent waterproof access opening in the top of each tunnel
                                     section to allow installation and removal of tunnel equipment and 20 foot
                                     sections of pipe.
                               12.   Secure branch tunnel connectors to building basement mechanical rooms
                                     with six (6) inch concrete masonry block walls and lockable metal access
                                     doors.
                               13.   Design tunnel penetrations to accommodate expansion and contraction
                                     without compromising the waterproof integrity of the tunnel.
                               14.   Design tunnels with code required ventilation system. Provide steel grated
                                     ventilation openings with security locks bolted from inside the tunnel.
                      B.       UNDERGROUND DIRECT-BURY PIPING:
                               1.    When the campus site layout, topography, subsurface geology or other
                                     conditions prohibit the construction of utility tunnels, use direct-bury pre-
                                     insulated piping for campus chilled water and heating hot water piping
                                     distribution. Provide a minimum of six (6) inches clearance between
                                     outside of insulation of individual pipes for future maintenance.
                               2.    Provide concrete vaults for valves and taps and use the designs that are
                                     appropriate for tunnels.
                               3.    Bury underground systems in a trench not less than four (4) feet deeper
                                     than the top of the pipe and not less than 36 inches wider than the
                                     combined outside diameter of all piping systems. Provide a minimum
                                     thickness of 36 inches of compacted backfill with no rocks or stones or
                                     other debris larger than two (2) inches placed over the top of the pipe to
                                     meet H-20 highway loading.
                               4.    Provide trench bottom with a minimum of 12 inches of sand fill material as
                                     a cushion for the piping. Cover the top of the pipe a minimum of 12 inches
                                     with a sand fill material as a cushion for the piping. Install a brightly colored
                                     blue plastic marker above and extending completely across the entire width
                                     of the buried piping in the trench plus six (6) inches on each side between
                                     the 12 inches top fill and the 36 inches of compacted backfill.

23.08    MECHANICAL SYSTEMS

         23.08.1          HANGERS, SUPPORTS AND SLEEVES
                          A.   Design piping systems to utilize pipe hangers, inserts, and supports in
                               conformance with the International Mechanical Code, MSS SP-58 and MSS SP-
                               69. Provide hangers fabricated to permit adequate vertical adjustment of 1-1/2-
                               inch minimum after installation while still supporting the load. Support piping
                               subjected to vertical movement with variable spring hangers and supports, or by


Issued January 31, 2009                                                                                23 00 00 11/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               constant support hangers. The use of pipe hooks, chains, or perforated iron for
                               pipe supports will not be accepted.
                          B.   Support horizontal cast iron pipe adjacent to each hub, with a maximum of five
                               (5) foot spacing between hangers. Support vertical cast iron pipe at each floor at
                               hub.
                          C.   Provide pipe hangers within 12 inches of each change in direction and provide
                               hangers on both sides of line valves.
                          D.   Support vertical piping at each floor. For pipe risers exceeding three (3) floors,
                               evaluate pipe supports for longitudinal expansion and support requirements.
                               Support riser piping independently of connected horizontal piping.
                          E.   Support ductwork in accordance with SMACNA requirements.
                          F.   Provide four (4) inch high concrete housekeeping pads and equipment bases for
                               outdoor equipment on grade, indoor floor mounted equipment in main central
                               plant area, equipment in areas with floors below grade, penthouse equipment
                               rooms and in any mechanical room. Extend housekeeping pads and supports a
                               minimum of six (6) inches beyond the equipment or supported member in all
                               directions. Provide pads with 1/2 inch chamfer on all exposed edge, placed and
                               finished smooth and level to insure proper and continuous support for the
                               bearing surfaces of the equipment.
                          G.   Provide prefabricated factory insulated curbs for roof-mounted equipment, a
                               minimum of 12 inches in height above the finished roof surface. Provide curb
                               pitched to match roof slope if required.
                          H.   Provide pipe sleeves for all ductwork and pipe penetrations through wall, roof or
                               floors. Provide sleeves one size larger than the pipe it serves (accounting for
                               insulation) or one (1) inch larger in all dimensions for ductwork, including
                               insulation. Provide sleeves in non-load bearing surfaces fabricated of
                               galvanized sheet metal, and sleeves in load bearing surfaces constructed of
                               uncoated carbon steel pipe. Sleeves shall not be installed in structural
                               members. Seal all sleeves water and airtight. Provide UL listed sealant between
                               pipe and sleeve as required by code. Provide escutcheon around penetrations
                               in finished areas.
                          I.   Provide Linkseal (or approved equal) assembly for pipe penetrations through
                               waterproofed floors and walls.
                          J.   Where piping or ductwork penetrates floor, ceiling or wall, close off space
                               between pipe and ductwork and adjacent work with fire stopping insulation and
                               seal airtight. Provide escutcheon covers at both sides of penetration. When
                               penetration is through a fire rated floor or wall, provide fire-safe insulation so
                               that the assembly, when complete, is UL listed and equals the fire rating of
                               construction penetrated by the sleeve.
                          K.   Provide concrete-filled spring-isolated inertia bases installed on top of concrete
                               housekeeping pad for rotating mechanical equipment, including but not limited
                               to fans, pumps, etc.
         23.08.2          CHIMNEYS AND STACKS
                          A.   Provide double wall pre-insulated boiler stack piping per the following
                               requirements. In lieu of double wall stack piping, insulate boiler stacks as well as
                               diesel engine exhaust pipe in accordance with Table 23.08.2.
                          B.   For stacks six (6) inches and less, specify double-wall, factory-built type vent
                               pipe, tested in accordance with UL 441, for use with approved Category I
                               appliances burning natural or LP gas, which produce flue gases exhausted at


Issued January 31, 2009                                                                              23 00 00 12/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               temperatures not exceeding 550º F, with inner jacket of aluminum alloy and
                               outer jacket of galvanized steel.
                          C.   For stacks greater than six (6) inches in diameter, specify double wall, factory-
                               built type metal stacks, tested to UL 103 for use with equipment burning
                               gaseous, liquid, or solid fuels, rated in accordance with NFPA 211, with type
                               316 stainless steel inner and outer walls. Stack to be listed for internal static
                               pressures of 60 inches water gage. Provide with one (1) inch ceramic fiber
                               insulation between the inner and outer walls.
                          D.   For condensing boilers and direct vent equipment, specify double wall, factory-
                               built type metal vent, tested to UL 1738 for use with condensing appliances or
                               pressurized venting systems serving Category II, III, or IV appliances or as
                               specified by the equipment manufacturer with a maximum temperature not to
                               exceed 550ºF. Specify with one (1) inch minimum air space between walls,
                               inner jacket of AL-29-4C superferritic stainless steel and outer jacket of Type
                               316 stainless steel. Stack to be listed for an internal static pressure of 6 inches
                               water gage and tested to 15 inches water gage. Provide with one (1) inch
                               ceramic fiber insulation between the inner and outer walls.
                          E.   Provide accessories each bearing factory applied UL label: Ventilated Roof
                               Thimble, consisting of roof penetration, vent flashing with spacers and storm
                               collar; Exit Cone, consisting of inner cone, and outer jacket, to increase stack
                               exit velocity 1.5 times and Stack Cap, consisting of conical rainshield with
                               inverted cone for partial rain protection with low flow resistance.
                          TABLE 23.08.2 – BOILER STACK AND DIESEL ENGINE EXHAUST INSULATION

                           SERVICE AND                                     OUTSIDE DIAMETER (INCHES)
                           SURFACE              INSULATION
                           TEMPERATURE          MATERIAL           <1.25    1.5 to 3   3.5 to 5   6 to 10   11 to 36
                           RANGE
                           Boiler Stack         Mineral Fiber       2.5       2.5        3.0       3.5         4.0
                           (Up to 400ºF)        Calcium Silicate    2.5       2.5        3.0       3.5         4.0
                           Boiler Stack         Mineral Fiber       2.5       2.5        4.0       4.0         5.0
                           (401 to 600ºF)       Calcium Silicate    2.5       2.5        4.0       4.0         5.0
                           Boiler Stack         Mineral Fiber       2.5       2.5        4.0       4.0         6.0
                           (601 to 800ºF)       Calcium Silicate    2.5       2.5        4.0       4.0         6.0
                           Diesel Engine
                           Exhaust              Calcium Silicate    3.0       3.5        4.0       4.0         6.0
                           (Up to 700ºF)


         23.08.3          SOUND AND VIBRATION CONTROL
                          A.   Design mechanical equipment along with associated piping and ductwork to be
                               installed with vibration isolation devices, as required, to minimize the
                               transmission of noise and vibration transmitted to the building structure or
                               adjacent spaces in accordance with Chapter 47 of the 2003 ASHRAE Handbook
                               – HVAC Applications.
                          B.   Provide flexible connectors between ductwork and connections to air handling
                               equipment.
                          C.   Provide Kevlar reinforced rubber double-sphere flanged flexible connectors
                               (Mason SFDEJ or equal) for pipe connections greater than two (2) inches to
                               rotating mechanical equipment. Provide braided stainless steel flexible pipe
                               connectors for pipe connections two (2) inches in diameter and less.
                          D.   Design equipment, supports and connections so that maximum interior sound
                               pressure levels do not exceed the levels set forth in Table 34 in Chapter 47 of


Issued January 31, 2009                                                                               23 00 00 13/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               the 2003 ASHRAE Handbook – HVAC Applications. Coordinate construction
                               requirements with the Design Professionals to ensure conformance.
                          E.   Design outdoor equipment to comply with local noise ordinances.

         23.08.4          MECHANICAL IDENTIFICATION
                          A.   Identify and label mechanical equipment, piping, ductwork, valves and
                               accessories per the following requirements.
                          B.   Use the systems and equipment identification scheme in a consistent manner
                               for project design, and indicate with designated format on design Drawings and
                               Specifications, piping and instrumentation diagrams (P&IDs), sketches,
                               schedules, and on component tags and labels. The same identification format
                               will be applied to the Graphical User Interface (GUI) through the BAS.
                          C.   EQUIPMENT/COMPONENT IDENTIFICATION:
                               1.   Identify each individual piece of equipment (pump, chiller, valve,
                                    instrument, panel, etc.) with a unique tag number.
                               2.   Utilize two (2) distinct formats for campus systems identification: Central
                                    Plant and Building Systems.
                                     a. The Central Plant identification scheme will apply to all equipment and
                                          systems (e.g. chillers, boilers, piping, pumps, temperature sensors,
                                          controllers, valves) contained within or originating from the central
                                          plant, including those systems that extend throughout the campus to
                                          serve multiple buildings.
                                     b. The Building identification scheme will apply to equipment, systems
                                          and accessories (e.g. piping, pumps, temperature sensors,
                                          controllers, air handlers, dampers, ductwork, air terminal units)
                                          contained within a building, downstream of and including the building
                                          tertiary chilled water and heating hot water pumps.
                                     c. The line of demarcation between the central plant identification
                                          scheme and the building identification scheme will be the building
                                          tertiary chilled water and heating hot water pumps.
                                     d. Provide a legend on the Drawings to clearly indicate the identification
                                          scheme methodology and tabulate all system code and component
                                          identifiers used for the systems and equipment.
                               3.   CENTRAL PLANT IDENTIFICATION SCHEME:
                                    a. The elements of the Central Plant Identification Scheme for
                                       equipment, components and accessories are:
                                         Campus-System-Component-ID Number/Alphanumeric
                                         Campus Code:    2 letter system designation for campus (DT, NE,
                                                         NW, SE, SO).
                                         System Code:    2/3 letter system designation (e.g. CHW for
                                                         chilled water, CW for condenser water, A/C for
                                                         air conditioning). Develop component codes
                                                         consistent with TCCD standards and ISA
                                                         standard S5.1.
                                         Component Code: Multiple letter designation dependent on
                                                         device/equipment function (e.g. TT for
                                                         temperature transmitter, PMP for pump, LI for
                                                         level indicator, CV for control valve). Develop
                                                         component codes consistent with TCCD
                                                         standards and ISA standard S5.1.

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                    ID/Alphanumeric:       Three (3) digit number, where first digit indicates
                                                           the loop and the next two (2) digits are
                                                           sequential within the loop so that each loop
                                                           component has a unique identifier. Alpha
                                                           character is used to distinguish between
                                                           redundant instruments. Example: DT-CW-PT-
                                                           200A and DT-CW-PT-200B.
                                    Examples:              DT-CW-CT-200.
                                                           Downtown campus cooling tower cell number
                                                           two in the condenser water system.
                                                           DT-CW-VLV-202.
                                                           Downtown campus condenser water return
                                                           isolation valve for cooling tower cell number two.
                                                           DT-CW-CIT-012.
                                                           Downtown campus condenser water system
                                                           conductivity indicating transmitter.
                               b.   Label central plant and main campus distribution piping on the P&IDs,
                                    and compile complete and accurate line listing at the completion of
                                    design for TCCD piping management. The elements of the Central
                                    Plant Identification Scheme for piping are:
                                    Size-System-Class/Material/Insulation-ID Number-Campus
                                    Size:                 Nominal pipe diameter.
                                    System:               2/3 letter system designation (e.g. CHW for
                                                          chilled water, CW for condenser water).
                                                          Develop component codes consistent with
                                                          TCCD standards and ISA standard S5.1.
                                    Class:                ANSI pipe pressure ratings coded as follows:
                                                               A: 125
                                                               B: 150
                                                               C: 300
                                    Material:             Piping material coded as follows:
                                                               A: Carbon Steel
                                                               B: Stainless Steel
                                                               C: Copper
                                                               D: PVC
                                                               E: Ductile Iron
                                                               F: Polyethylene
                                                               G: Other
                                    Insulation:           Insulation material coded as follows:
                                                               A: Mineral fiber or preformed fiberglass
                                                               B: Molded cellular glass
                                                               C: Calcium silicate
                                                               D: Rigid Phenolic
                                                               E: Polyisocyanurate
                                    ID Number:            Sequential number.
                                    Campus Code:          2 letter system designation for campus (DT, NE,
                                                          NW, SE, SO).
                                    Example:              8”-CHW-BAD-001-DT.
                                                          8-inch chilled water line, 150# class carbon steel
                                                          with rigid phenolic insulation, Downtown
                                                          Campus.
                          4.   BUILDING SYSTEMS IDENTIFICATION SCHEME:

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                    a.   The elements of the Building Systems Identification Scheme for
                                         equipment, components and accessories are:
                                         Campus-Building-Room-System-Component-Alphanumeric
                                         Campus /Building: 4 letter system designation for campus/building
                                                           (DBUS, NHPE, WACB, ESEE, SBSA).
                                         Building:         Building code as defined by TCCD.
                                         Room:             Room/area containing equipment ie 1103A.
                                         System Code:      2/3 letter system designation (e.g. CHW for
                                                           chilled water, CW for condenser water, A/C for
                                                           air conditioning). Develop component codes
                                                           consistent with TCCD standards and ISA
                                                           standard S5.1.
                                         Component Code: Multiple letter designation dependant upon
                                                           device/equipment function (see above).
                                         Alphanumeric:     Three (3) digit number, where first digit indicates
                                                           the loop and the next two digits are sequential
                                                           within the loop so that each loop component has
                                                           a unique identifier. Alpha character is used to
                                                           distinguish between redundant instruments.
                                                           Example:       DBUS-1103A-CW-PT-200A           and
                                                           DBUS-1103A-CW-PT-200B.
                                         Example:          DBUS–1103A-A/C-AHU-200
                                                           Air handling unit number two installed in room
                                                           1103A in the Downtown Campus Business
                                                           building, part of the air conditioning system.
                          D.   LABELING REQUIREMENTS:
                               1.   Specify equipment identification tags fabricated of laminated three-layer
                                    plastic with engraved white letters on a black background; minimum size 3
                                    inches long by 1 inch high. Minimum lettering height for numbers and
                                    names is 1/4-inch; other data is 1/8-inch. Mechanically fasten tags to
                                    equipment using screws or rivets. Specify tags to identify equipment
                                    unique identifier, function, capacity, and other pertinent information for
                                    future maintenance.
                               2.   Label plumbing and mechanical piping systems in accordance with Table
                                    23.08.4-A. Identify pipe flow directions using arrows.

                               TABLE 23.08.4-A – PLUMBING AND MECHANICAL PIPING SYSTEMS
                                                  LABELING

                                                                                    LETTERS/
                                SERVICE                                BAND         ARROW        LEGEND
                                Domestic cold water (potable)          Lt. Blue     White        DCW
                                Domestic hot water                     Orange       White        DHW
                                Domestic hot water return              Orange       White        DHWR
                                Fire protection water                  Red          White        FIRE
                                Condenser water supply                 Brown        White        CWS
                                Condenser water return                 Brown        White        CWS
                                Primary chilled water supply           Dark Blue    White        PCHS
                                Primary chilled water return           Lt. Blue     White        PCHR
                                Secondary chilled water supply         Dark Blue    White        SCHS
                                Secondary chilled water return         Lt. Blue     White        SCHR
                                Primary heating hot water supply       Orange       White        PHWS
                                Primary heating hot water return       Orange       White        PHWR
                                Secondary heating hot water supply     Orange       Black        SHWS

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                                                                      LETTERS/
                                SERVICE                                 BAND          ARROW        LEGEND
                                Secondary heating hot water return      Orange        Black        SHWR
                                Lab waste ACID                          Orange        Black        LAB WASTE
                                Lab vent ACID                           Orange        Black        LAB VENT
                                Deionized water                         Orange        Black        DI
                                Sanitary vent                           Green         White        VENT
                                Sanitary sewer                          Green         White        SS
                                Chemical feed                           Purple        Black        CHEM FEED
                                Compressed air                          Yellow        Black        COMP AIR

                                    a.   Paint insulation of exposed piping located within mechanical rooms.
                                         Pipe identification bands acceptable for use in concealed areas.
                                         Coordinate pipe and insulation painting preparation requirements with
                                         Design Professional.
                                    b. Specify underground piping, both mechanical and plumbing, to be
                                         installed with buried pipeline marker. Provide magnetic-type warning
                                         tape installed above the piping in the backfill at least six (6) inches
                                         below grade, imprinted to read "Caution- buried pipe below”.
                               3.   Provide pipe markers compatible with the requirements shown in Table
                                    23.08.4-B.
                                    a. Specify identification for valves by using a securely attached brass
                                         valve tag stamped with valve tag number. Provide valve schedule
                                         identifying valve number and function.
                               4.   Identify ductwork with stenciled painting. Identify as to air handling unit
                                    number and area served. Locate identification at air handling unit, at each
                                    side of penetration of structure or enclosure and at each obstruction.

                               TABLE 23.08.4-B – PIPE MARKERS

                                                                                                 SIZE OF
                                                                LENGTH OF      ARROW             LEGEND
                                OUTSIDE DIAMETER OF             COLOR          LENGTH BY         LETTERS AND
                                PIPE COVERING                   BAND           WIDTH             NUMERALS
                                (INCHES)                        (INCHES)       (INCHES)          (INCHES)
                                Less than 1-1/2                 8              8x1               1/2
                                1-1/2 to 2-3/8                  8              8 x 2-1/4         3/4
                                2-1/2 to 7-7/8                  12             8 x 2-1/4         1-1/4
                                8 to 10                         24             12 x 4-1/2        2-1/2
                                Over 10                         32             12 x 4-1/2        3-1/2



23.09    MECHANICAL INSULATION

         23.09.1          GENERAL REQUIREMENTS
                          A.   Specify insulation and associated accessories to have a maximum flame spread
                               index of 25 and a maximum smoke developed index of 50 when tested in
                               accordance with ASTM E 84.
                          B.   Specify insulation thickness and thermal conductivity (k-value) in conformance
                               with the latest edition of ASHRAE 90.1 as accepted by the Texas State Energy
                               Conservation Office (SECO).
                          C.   Design duct and pipe insulation to be continuous through walls, partitions,
                               ceiling openings and sleeves.

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          D.   Specify UL-approved assemblies for pipes and ducts passing through fire-rated
                               floors, walls, or partitions as required.
                          E.   Apply insulation on all cold surfaces with a continuous, unbroken vapor seal.
                               Guides and anchors secured directly to cold surfaces must be adequately
                               insulated and vapor sealed to prevent condensation.
                          F.   Seal edges of vapor barrier insulation at valve stems, instrument wells, unions
                               and other raw edges to prevent moisture from penetrating the insulation.
                          G.   Provide insulation protection shields fabricated from galvanized steel at all pipe
                               hangers in accordance with MSS-SP69.
                          H.   Provide aluminum jackets for exterior pipe, ductwork, and equipment insulation
                               covers, as well as for exposed piping in mechanical rooms subject to wear or
                               abuse.
                          I.   Avoid the use of internal duct liner in air ductwork for long term Indoor Air
                               Quality. The Design Professional shall coordinate this section with the FB.
         23.09.2          DUCTWORK INSULATION, EXTERIOR TO BUILDING
                          A.   Provide ASTM C 591 Type I, polyisocyanurate board insulation, minimum
                               density of 1.7 pounds per cubic foot, with aluminum jacket sealed water tight.
                               Cant insulation on top of duct to promote drainage.
         23.09.3          DUCTWORK INSULATION, INTERIOR: CONCEALED OR EXPOSED
                          A.   Specify two (2) inch rigid mineral fiber in accordance with ASTM C 612, Class 2
                               (maximum surface temperature 400ºF), 3 pounds per cubic foot average
                               density, Type IA, IB, II, III, and IV. Provide with foil scrim kraft facing for air
                               ducts. No interior duct insulation.
                          B.   Specify two (2) inch flexible mineral fiber blanket insulation conforming to ASTM
                               C 553, Type 1, Class B-3, 3/4 pound per cubic foot nominal density, or Type II
                               up to 250ºF. Also ASTM C 1290 Type III may be used. Provide with foil scrim
                               kraft facing for air ducts.
         23.09.4          PIPE INSULATION
                          A.   RIGID PHENOLIC INSULATION: ASTM C 1126, Type II or II, Grade I, to 250ºF
                               service, 'k' value of 0.13 at 75ºF. Provide CFC-free, closed cell insulation, with
                               factory-applied jacket.
                          B.   POLYISOCYANURATE INSULATION: ASTM C 591, Type 1, to 300ºF service.
                               Supply the insulation with manufacturer's recommended factory applied jacket.
                               Provide aluminum jacket for exterior applications.
                          C.   MINERAL FIBER OR FIBERGLASS PREFORMED INSULATION: ASTM C
                               547, 'k' value of 0.26 at 75ºF; noncombustible, with factory applied white kraft
                               foil vapor barrier.
                          D.   FLEXIBLE ELASTOMERIC CLOSED CELL INSULATION: ASTM C 534,
                               Grade 1, Type I or II. Type II shall have vapor retarder skin on one or both
                               sides of the insulation.
                          E.   Insulate piping systems per Table 23.09.1. Provide color-coded PVC jackets for
                               piping in mechanical rooms. Coordinate colors with Table 23.08.4-A.

                          TABLE 23.09.1 – PIPE INSULATION




Issued January 31, 2009                                                                             23 00 00 18/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                                                                                              Vapor
                                                                                   ASTM                       BARRIER
                           Service                          Material                              Type
                                                                                   Spec.                      Required
                           Chilled Water Supply & Return,
                                                            Rigid Phenolic         C1167          II/III      Yes
                           Interior Application
                           Chilled Water Supply & Return,
                                                            Polyisocyanurate       C 591          I           Yes
                           Exterior Application
                                                            Insulation is not required for piping over ten (10) inches in
                                                            diameter for exterior installation. Paint exposed piping on
                                                            roof and in mechanical rooms in accordance with
                           Condenser Water Supply &
                                                            mechanical identification requirements indicated in
                           Return
                                                            previous section. Match requirements of chilled water
                                                            piping for pipes ten inches in diameter or less in exterior
                                                            applications.
                           Heating Hot Water Supply &
                                                            Fiberglass             C 547          I           No
                           Return (Max. 250ºF)
                           Cold Domestic Water, Makeup      Flexible
                           Water & Drinking Fountain        Elastomeric            C 534          I           No
                           Drain Piping                     Cellular
                           Hot Domestic Water Supply &
                           Re-circulating Piping (Max.      Fiberglass             C 547          I           No
                           200ºF)
                                                            Flexible
                           Refrigerant Suction Piping       Elastomeric            C 534          I           Yes
                                                            Cellular
                           Exposed Lavatory, Exposed        Flexible
                           Domestic Water Piping & Drains   Elastomeric            C 534          I           No
                           to ADA Areas                     Cellular
                           Horizontal Roof Drain Leaders
                           (Including Underside of Roof     Fiberglass             C 547          I           Yes
                           Drain Fittings)
                           Cold Condensate Drain Located
                                                            Rigid Phenolic         C1167          II/III      Yes
                           Inside Building

         23.09.5          EQUIPMENT INSULATION

                          A.   Do not insulate over nameplate or ASME stamps. Bevel and seal insulation
                               around nameplates.
                          B.   Provide flexible reusable insulation blankets for equipment requiring access
                               such as pumps, valves, strainers, etc.
                          C.   EQUIPMENT INSULATION MATERIALS:
                               1.   MINERAL FIBER: ASTM C 547, Types I, II or III; supply the insulation with
                                    manufacturer's recommended factory-applied jacket.
                               2. CALCIUM SILICATE: ASTM C 533, Type I indoors only, or outdoors above
                                    250ºF pipe temperature.        Supply insulation with the manufacturer's
                                    recommended factory-applied jacket.
                               3. FLEXIBLE ELASTOMERIC CELLULAR INSULATION: ASTM C 534,
                                    Grade 1, Type I or II. Type II with vapor retarder skin on one or both sides
                                    of the insulation.
                          D.   Insulate the following equipment: cold refrigeration equipment parts that are not
                               factory insulated, drip pans under chilled equipment, cold water storage tanks,
                               water softeners, duct mounted coils, cold and chilled water pumps, roof drain
                               bodies, air handling equipment parts that are not factory insulated, expansion
                               and air separator tanks, heat exchangers, hot water generators, water heaters,
                               pumps handling media above 130ºF, hot water storage tanks, surge tanks,



Issued January 31, 2009                                                                                    23 00 00 19/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                  unjacketed boilers or parts of boilers, boiler flue gas connection from boiler to
                                  stack (if inside), induced draft fans, boiler stacks, and diesel engine exhaust.
                          E.      Insulate equipment in accordance with Table 23.09.5:


                          TABLE 23.09.5 – EQUIPMENT INSULATION


                               EQUIPMENT HANDLING
                               MEDIA AT INDICATED              INSULATION MATERIAL                  THICKNESS
                               TEMPERATURE
                                                              Flexible Elastomeric Cellular
                               1 to 34ºF
                                                                                                      1.5 inches

                               35 to 60ºF
                                                              Flexible Elastomeric Cellular           1.0 inches
                                                              Mineral Fiber                           2.0 inches
                               61 to 250ºF
                                                              Calcium Silicate                        2.0 inches
                                                              Mineral Fiber                           3.0 inches
                               251 to 400ºF
                                                              Calcium Silicate                        4.0 inches
                                                              Mineral Fiber                           4.0 inches
                               401 to 600ºF
                                                              Calcium Silicate                        6.0 inches
                                                              Thickness necessary to limit external temperature of the
                               >600ºF
                                                              insulation to 120oF.

23.10    PIPE AND PIPE SPECIALITIES

         23.10.1          GENERAL REQUIREMENTS
                          A.      Welding, welder qualification and welding procedure qualification shall be in
                                  accordance with ASME Section IX.
                          B.      Provide means for access where valves and fittings are not exposed.
                          C.      Specify hydrostatic pressure test to be performed at one and one-half times
                                  normal system operating pressure for a minimum of two (2) hours. Remove
                                  trapped air from system prior to test.
                          D.      Keep interior of all pipe, fittings, valves and accessories free from dirt and
                                  foreign material. Use suitable bulkheads to block or plug ends of piping during
                                  construction. Should dirt, mud, concrete, paint or other foreign materials be
                                  allowed to enter the piping or any section of piping, immediately clean prior to
                                  continuation.
         23.10.2          HYDRONIC PIPING, ABOVE GROUND (Chilled Water, Condenser Water &
                          Heating Hot Water)
                          A.      Pipe 2-1/2 inches and smaller, copper ASTM B 88, type L, hard drawn.
                                  1.   JOINTS: Two (2) inch diameter and smaller, soldered with ASTM B 32,
                                       grade Sb5 tin-antimony alloy (lead free) with ASTM B 813 solder flux. 2-
                                       1/2-Inch diameter, brazed using AWS A5.8, Type BAg-5 with AWS A5.31
                                       flux, except Type BCuP-5 or BCuP-6 may be used for brazing copper-to-
                                       copper joints.
                                  2. FITTINGS: Wrought copper and bronze fittings conforming to ASME
                                       B16.22 or cast bronze fittings conforming to ASME B16.18.
                          B.      Pipe three (3) inches to ten (10) inches; black steel pipe, ASTM A 53, grade B,
                                  Schedule 40, in accordance with ASME B36.10M. Pipe twelve (12) inches and
                                  larger; standard schedule.


Issued January 31, 2009                                                                                  23 00 00 20/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               1.   JOINTS: Two (2) inch diameter and smaller, threaded in accordance with
                                    ASME B1.20.1 or socket welded. 2-1/2-Inch diameter and larger, butt-
                                    welded.
                               2.   FITTINGS: Two (2) inch diameter and smaller, ASTM A 105/A 105M, in
                                    accordance with ASME B16.11. 2-1/2-Inch to 10-Inch Diameter, ASTM A
                                    234/A 234M, WPB(W), butt-weld, Schedule 40, in accordance with ASME
                                    B16.9. Twelve (12) inch diameter and larger, ASTM A 234/A 234M,
                                    WPB(W), butt weld, standard wall in accordance with ASME B16.9.
                               3.   FLANGED CONNECTIONS: Flanges in conformance with ASME B16.1,
                                    Class 150, with non-asbestos compressed material in accordance with
                                    ASME B16.21, 1/16-inch thickness, full face or self-centering flat ring type.
                                    Specify bolts, nuts, and bolt patterns in accordance with ASME B16.1.
         23.10.3          HYDRONIC PIPING, BELOW GROUND
                          A.   DIRECT BURIED HYDRONIC PIPING: Factory pre-insulated steel piping
                               suitable for direct burial at temperatures up to 230ºF, for underground chilled
                               and heating hot water campus distribution. Provide Schedule 40 piping with
                               closed cell polyurethane foam insulation having a minimum thermal conductivity
                               of 0.14 BTU inch/hour-square foot-ºF and an extruded black, high-density
                               polyethylene (HDPE) jacket with a minimum thickness of 125 mils. Provide
                               factory prefabricated and pre-insulated fittings with jacket identical to pipe
                               sections.
                          B.   UNDERGROUND CONDENSOR WATER PIPE: ASTM A 53. Grade B, 0.375-
                               inch wall for sizes twelve (12) inches and over in accordance with ASME
                               B36.10M. Joints, fittings, and valves shall be as specified for aboveground
                               piping.
                               1.   Provide cathodic protection on all underground condenser water piping,
                                    installed in accordance with manufacturer’s recommendations.
         23.10.4          AUXILIARY SYSTEMS PIPING
                          A.   EQUIPMENT DRAINS AND OVERFLOWS: Copper ASTM B 88, Type K, hard
                               drawn with ASME B16.23 cast brass, or ASME B16.29 solder wrought copper
                               and ASTM B 32, Grade Sb5 soldered joints.
                          B.   CHEMICAL FEED: Schedule 80 PVC, drawn stainless steel tubing with
                               Swagelock fittings or polyethylene, as recommended by chemical treatment
                               vendor.
                          C.   COLD WATER MAKEUP PIPING: Type K hard drawn seamless copper tubing
                               with joints soldered with ASTM B 32, grade Sb5 tin-antimony alloy (lead free)
                               with ASTM B 813 solder flux or brazed with AWS A5.8, type Bag-5 with AWS
                               type 3 flux, except type BCuP-5 or BCuP-6 may be used for brazing copper-to-
                               copper joints. Provide with wrought copper fittings conforming to ASME B16.22.
                               1.   Provide a reduced pressure backflow preventer on cold water makeup
                                    connections. Evaluate system pressures to ensure adequate flow delivery
                                    capacity is available.
                               2.   Refer to Chapter 25, Controls, for makeup water metering requirements.
         23.10.5          VALVES
                          A.   Provide valves of same manufacturer throughout the project where possible.
                          B.   Provide valves with manufacturer's name and pressure rating clearly marked on
                               outside of body.



Issued January 31, 2009                                                                            23 00 00 21/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          C.   Provide access panels to accommodate service of all valves installed inside
                               walls or other concealed areas.
                          D.   Provide valve vaults or valve boxes, as conditions warrant, to provide actuator
                               access for valves installed below ground.
                          E.   GLOVE AND ANGLE VALVES: Provide valves 2-1/2 inches and smaller in
                               accordance with MSS SP-80, Class 125. Provide globe and angle valves three
                               (3) inches and larger in accordance with MSS SP-85, Class 125.
                          F.   CHECK VALVES: Provide check valves 2-1/2 inches and smaller in accordance
                               with MSS SP-80. Provide check valves three (3) inches and larger in
                               accordance with MSS SP-71, Class 125.
                               1.   Provide tilting disc type check valves with cast steel body and enclosed
                                    spring located in pump discharge piping.
                          G.   BUTTERFLY VALVES: Provide full lugged drilled and tapped for dead end
                               service type valves in accordance with MSS SP-67, Type 1. Provide throttling
                               handles with a minimum of seven (7) locking positions for valves smaller than
                               eight (8) inches. For valves eight (8) inches and larger, provide totally enclosed
                               manual gear operators with adjustable balance return stops and position
                               indicators.
                               1.    Provide high-performance double offset butterfly valves (Keystone K-LOK
                                     or approved equal) in central plant hydronic piping for flow isolation and
                                     balancing service. The Design Professional shall coordinate this section
                                     with the FB.
                          H.   PLUG VALVES: Provide plug valves two (2) inches and larger in accordance
                               with MSS SP-78, with flanged or threaded ends and cast iron bodies with
                               bronze trim. Provide valves two (2) inches and smaller fabricated of bronze with
                               NPT connections for black steel pipe and brazed connections for copper tubing.
                               Provide non-lubricated, or tetrafluoroethylene resin-coated type. Valve shall be
                               resilient, double seated, trunnion mounted with tapered lift plug capable of 2-
                               way shutoff, capable of operating from fully open to fully closed, by rotation of
                               the handwheel to lift and turn the plug. Provide manual gear operators with
                               position indicators for valves eight (8) inches and larger.
                          I.   BALL VALVES: Provide full port design; ball valves 1/2 inch and larger in
                               accordance with MSS SP-72 or MSS SP-110, cast iron or bronze with threaded,
                               soldered, or flanged ends. Provide valves eight (8) inches and larger with
                               manual gear operators with position indicators.
                          J.   PUMP DISCHARGE (TRIPLE DUTY) VALVE: Triple duty valve to perform the
                               functions of a non-slam check valve, a manual balancing valve, and an isolation
                               valve. Provide valve fabricated of cast iron or ductile iron construction with
                               bronze and/or stainless steel accessories, with an integral pointer on the valve.
                               Allow flow through the valve to be manually adjustable from bubble tight shutoff
                               to full flow. Provide flanged end connections for valves two (2) inches and
                               larger, and allow the back seat for the stem to be replaced in the field under full
                               line pressure.
                               1.   Provide triple duty valves in tertiary pump discharge piping.
                          K.   Provide butterfly isolation valve downstream of triple duty valves to allow valve
                               maintenance.
                          L.   RELIEF VALVES: Steel body, direct spring operated, soft seat, 150 pound,
                               flanged ends, in accordance with ASME Section VIII.
                          M.   PRESSURE INDEDENDENT CONTROL VALVES: Provide pressure
                               independent modulating control valves (Belimo or Flow Control Industries Delta

Issued January 31, 2009                                                                             23 00 00 22/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               P model with ports). The control valves shall accurately control the flow from 0
                               to 100% full rated flow, and flow through the valve shall not vary more than +/-
                               5% due to system pressure fluctuations across the valve in the selected
                               operating range.
                               1.   Provide flow tag with each valve listing flows at all the valve positions in 10
                                    degree rotation increments.
                               2.   Range ability of the control valves shall be 100:1 minimum, rated at the full
                                    differential pressure provided by the tertiary pump serving the hydronic
                                    loop in which control valve is installed.
                               3.   Provide control valves with close off pressure equaling one and a half times
                                    the pressure rating of the valve.
                               4.   Provide valve bodies two (2) inches in diameter and smaller fabricated of a
                                    bronze body, rated for 150 psig working pressure, with bronze trim, rising
                                    stem, handwheel, inside screw, renewable composition disc, solder or
                                    screwed ends, with back seating capacity (re-packable under pressure).
                               5.   Provide valve bodies 2-1/2 inch diameter and larger fabricated of a cast
                                    iron body, rated for 150 psig working pressure, with bronze trim, rising
                                    stem, handwheel, outside stem and yolk, plug-type disc, flanged ends,
                                    renewable composition seat and disc. Valve flow characteristics shall be
                                    able to be changed without removing the valve from the piping system.
                               6.   Provide electronic actuators to be shipped to valve manufacturer for
                                    mounting and calibration. The valve manufacturer shall set the stroke of
                                    the actuator at full design flow from performance curves furnished with
                                    each valve. Actuators for valves six (6) inches and smaller modulate the
                                    control valve for 0 to 100% of design flow while rotating a maximum of 90º.
                               7.   Furnish control valve with flow adjustment stem extending up from the
                                    control valve. Control valve shall be provided with mounting holes for
                                    control actuator bracket. Valve stem is rotated by actuator to provide the
                                    required flow. Torque requirements to be defined by control valve
                                    manufacturer based on specified valve model.
                               8.   Furnish valve with three (3) factory installed 1/4-inch NPT ports; two (2)
                                    ports used to measure inlet and outlet pressure, the remaining port to be
                                    used during calibration to measure internal pressure within the valve to
                                    confirm flow rate through the valve.
                               9.   Provide differential pressure transmitters installed across inlet and outlet
                                    pressure ports to communicate pressure differential to the BAS for flow
                                    measurement calculation.
         23.10.6          HYDRONIC SPECIALTIES
                          A.   AIR SEPERATORS: Steel, tested and stamped in accordance with ASME SEC
                               VIII, 125 psig operating pressure, with tangential inlet and outlet connections
                               and internal stainless steel air collector tube. Provide air separators on the
                               pumps suction side of campus and building main distribution pump headers.
                          B.   EXPANSION TANKS: Welded steel closed bladder type, tested and stamped in
                               accordance with ASME SEC VIII, rated for working pressure of 125 psig, with
                               replaceable flexible heavy-duty butyl bladder, pressure gauge and steel support
                               stand.
                          C.   PUMP SUCTION FITTING: Angle type body with removable strainer basket and
                               internal straightening vanes, integral adjustable support, with casing connection
                               sizes to match pump suction and inlet pipe sizes. Provide with a blowdown
                               outlet and plug, and strainer and permanent magnet located in flow stream and
                               removable for cleaning.


Issued January 31, 2009                                                                              23 00 00 23/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          D.   STRAINERS: Provide cleanable, basket or "Y" type, size to match piping.
                               Provide strainer bodies fabricated of cast iron with drilled and tapped bottoms,
                               blowoff outlet with pipe nipple, gate valve, discharge pipe nipple and cast arrows
                               indicating the direction of flow.
                          E.   FLEXIBLE PIPE CONNECTORS: Provide flexible stainless steel piping
                               connectors with single braid for piping connections to coils. Equip flanged
                               assemblies with limit bolts to restrict maximum travel to the manufacturer's
                               standard limits. Unless otherwise required, the length of the flexible connectors
                               shall be as recommended by the manufacturer for the service intended. Internal
                               sleeves or liners, compatible with circulating medium, shall be provided when
                               recommended by the manufacturer. Provide covers to protect the bellows where
                               indicated.
                          F.   Provide Kevlar reinforced EPDM double sphere type flexible pipe connectors
                               (Mason SFDEJ or approved equal) for connections to boilers, chillers, cooling
                               towers, pumps, etc. Connectors designed to provide volumetric response to
                               sound pressure waves and sound attenuation.
                          G.   AIR VENTS:
                               1.   Manually operated general service type air venting valves, brass or bronze
                                    valves, furnished with threaded plugs or caps.
                               2.   Automatic type air vents of ball-float type design with brass/bronze or brass
                                    bodies, 300 series corrosion-resistant steel float, linkage and removable
                                    seat.
         23.10.7          REFRIGERANT PIPING AND SPECIALTIES
                          A.   Provide refrigerant piping, valves, fittings, and accessories in accordance with
                               ASHRAE 15 and ASME B31.5.
                          B.   Provide isolation valves at all refrigeration specialties.
                          C.   PIPE: Copper tubing, ASTM B 280, type ACR, hard drawn with joints soldered
                               with ASTM B 32, grade Sb5 tin-antimony alloy (lead free) with ASTM B 813
                               solder flux or brazed with AWS A5.8, type Bag-5 with AWS A5.31 flux, except
                               type BCuP-5 or BCuP-6 may be used for brazing copper-to-copper joints.
                               Provide with wrought copper fittings conforming to ASME B16.22.
                          D.   Clean uncontaminated system(s) by evacuation and purging procedures
                               currently recommended by refrigerant and refrigerant equipment manufacturers
                               to remove small amounts of air and moisture. Systems containing moderate
                               amounts of air, moisture, contaminated refrigerant, or any foreign matter are
                               considered contaminated systems. Restoring contaminated systems to clean
                               condition including disassembly, component replacement, evacuation, flushing,
                               purging, and re-charging, to be performed using currently approved refrigerant
                               and refrigeration manufacturer's procedures.
                          E.   REFRIGERENT SPECIALITIES:
                               1.   MOISTURE AND LIQUID INDICATORS: Single port type, UL listed with
                                    copper or brass body, flared or solder ends, sight glass, color coded paper
                                    moisture indicator with removable element cartridge and plastic cap.
                               2.   REFRIGERENT FILTER DRIER: Driers shall conform to ARI 710 and shall
                                    be one direction flow with molded porous core to remove moisture and
                                    foreign matter from the refrigerant stream.
                               3.   EXPANSION VALVES: Provide valves in accordance with ARI 750 and
                                    ASHRAE 17. Valve shall be the diaphragm and spring-loaded type with



Issued January 31, 2009                                                                            23 00 00 24/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                    internal or external equalizers, bulb and capillary tubing, and an external
                                    superheat adjustment along with a seal cap.
                               4.   REFRIGERENT STOP VALVE: Globe or full-port ball type with a back-
                                    seating stem especially packed for refrigerant service, with replaceable
                                    valve packing, a hand wheel or wrench operator, and a seal cap. Provide
                                    straight or angle pattern valve as indicated.
                               5.   LIQUID SOLENOID VALVE: Provide direct-acting or pilot-operating valves
                                    in accordance with ARI 760, suitable for continuous duty with applied
                                    voltages 15% under and 5% over nominal rated voltage at maximum and
                                    minimum encountered pressure and temperature service conditions.
                                    Provide moisture-proof, UL approved, totally encapsulated or encapsulated
                                    and metal jacketed solenoid coils, with a working pressure of 400 psi and a
                                    maximum operating pressure differential of at least 200 psi at 85% rated
                                    voltage, and an operating pressure differential suitable for the refrigerant
                                    used.
                               6.   SAFETY RELIEF VALVE: Two-way type valve, bearing the ASME code
                                    symbol, with capacity certified by the National Board of Boiler and Pressure
                                    Vessel Inspectors. Valve to automatically reseat after activation.
                               7.   EVAPORATOR PRESSURE REGULATORS, DIRECT-ACTING: Include
                                    with diaphragm/spring assembly, external pressure adjustment with seal
                                    cap, and pressure gauge port. Valve to maintain a constant inlet pressure
                                    by balancing inlet pressure on diaphragm against an adjustable spring
                                    load.

23.11    PUMPS

         24.01.1          GENERAL REQUIREMENTS
                          A.   Provide pumps with motors, drives, mechanical seals, couplings, starters,
                               controls, suction strainers, pressure gauges, vibration isolation, check valves,
                               and isolation valves.
                          B.   Provide in-line vertical pump circulators or close-coupled end suction pumps for
                               low flow (up to 50 GPM) circulating systems.
                          C.   Provide base-mounted end suction pumps for circulating systems with flow rates
                               between 50 and 500 GPM.
                          D.   Provide horizontal spilt case, double-suction pumps for applications with flow
                               rates exceeding 500 GPM.
                          E.   Provide vertical turbine submersible pumps with TEFC Hazard-duty motors for
                               cooling tower concrete basin structures.
                          F.   Specify vertical in-line pumps for applications with limited floor space, with prior
                               approval of the FB.
                          G.   Provide pumps designed to operate at 1,750 rpm unless directed otherwise.
                          H.   Provide two (2) sets of strainers with pumps; a fine mesh startup strainer and a
                               final operating strainer.
                          I.   For centrifugal pumps, include certification that pump impeller diameter is less
                               than 85% of the range of impeller diameters available for the selected pump
                               casing, and that fabricated structural steel base is of sufficient strength to
                               prevent vibration, warping or misalignment of the pump.
                          J.   Provide pumps with grease lubricated ball bearings, grease fittings and relief
                               plugs.


Issued January 31, 2009                                                                              23 00 00 25/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          K.   Provide pumps to be free of flashing and cavitations at all flow rates between 25
                               and 125% of design flow under the suction conditions of the pump installation.
                          L.   Provide pumps sized for a critical speed of at least 115% of the operating speed
                               listed in the schedule.
                          M.   Provide flanged pump connections three (3) inches and larger; connections 2-
                               1/2 inches and less may be threaded.
                          N.   Select heating pumps suitable for handling water at 230ºF.
                          O.   Select motors to drive the pump through its characteristics curve from zero flow
                               to 125% of the design flow without exceeding the rated full load nameplate
                               horsepower. Provide with non-overloading motors, such that the rated
                               horsepower will not be exceeded at any point on the pump curve.
                          P.   Provide concrete filled inertia bases with open mount springs installed on top of
                               a concrete housekeeping pad for base-mounted pumps installed on floors
                               above grade.
                          Q.   Design pipe size changes off pumps using long radius reducing elbows or
                               eccentric reducers, while maintaining the top of pipe level. Support piping
                               adjacent to pump such that piping weight is not transferred to pump flanges or
                               casing. Provide supports under elbows attached to inertia bases on pump
                               suction and discharge elbows.
                          R.   Provide a minimum of five (5) straight pipe diameters at pump inlet connections,
                               unless a suction diffuser is used. Provide line size isolation valve and strainer
                               on pump suction piping. Provide line sized tilting disc check valve, (balancing
                               valve for non-VFD applications) and isolation valve on pump discharge piping.
                               A triple duty valve may be provided on the pump discharge line, along with a
                               separate isolation valve downstream of the triple duty valve.

23.12    WATER TREATMENT

         23.12.1          GENERAL REQUIREMENTS
                          A.   Coordinate with the FB to provide sample of site makeup use water for TCCD
                               chemical treatment company analysis to determine the best chemical treatment
                               system for the campus mechanical systems.
                          B.   Specify chemicals utilized for water treatment to meet required federal, state,
                               and local environmental regulations, and suitable direct discharge to the
                               sanitary sewer system.
                          C.   Provide makeup water lines with a water meter including a pulse generator, 4-
                               20 mA output for BAS interface, a remote readout register and necessary wiring
                               and accessories.
         23.12.2          PIPE CLEANING, GENERAL
                          A.   Obtain written approval of the chemical manufacturer for the cleaning and
                               flushing procedure. The chemical manufacturer representative will supervise
                               and certify in writing the cleaning and flushing of the piping systems.
                          B.   Provide systems which are operational, filled, started, and vented prior to
                               cleaning. Use water meter to record capacity in each system.
         23.12.3          PIPE CLEANING PROCEDURE
                          A.   Place coil control valves in open position during cleaning.
                          B.   Provide fine mesh temporary strainer screens in all system strainers.


Issued January 31, 2009                                                                           23 00 00 26/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          C.   Meter water flow into the pipe, and tabulate total system volume and provide
                               data to the FB.
                          D.   Add cleaner to piping of composition and concentration as recommended by
                               chemical company representative following the hydro test. Drain a water volume
                               equal to the calculated amount of added cleaner from the pipe.
                          E.   Remove all flow sensors and instruments sensitive to fouling during pipe
                               cleaning. Determine system flows based on pump differential and certified pump
                               curves.
                          F.   Flush the equipment to remove large debris at the maximum possible flow rate.
                               Fill the system to 80% design volume to allow room for expansion and
                               chemicals.
                          G.   Charge the Pre-Treatment products.
                          H.   Circulate the cleaning solution through the exchangers for 48 – 72 hours to
                               remove finishing oils and greases and passivate metallurgy. Have anti-foam
                               available in event of excess foaming.
                          I.   Flush with fresh water until the conductivity is reduced to that of the makeup
                               water and inspect the system. Inspect flanges, valves, or strainers. If the
                               system is still dirty repeat the process.
                          J.   Circulate the solution for 24 hours or as recommended by the FB’s
                               representative. Cleaner shall be circulated to maintain a minimum pipe flow as
                               shown in the following table. Following cleaning, drain systems as quickly as
                               possible. Refill with clean water, circulate for twelve (12) hours, then drain. Refill
                               with clean water and repeat until water quality is equal to city water.
                          K.   Remove temporary strainers.
                          L.   Inspect, remove sludge, and flush low points with clean water after cleaning
                               process is completed. Include disassembly of components as required.


                               TABLE 23.12.1 – MINIMUM CLEANING WATER FLOWS


                                              MINIMUM CLEANING WATER FLOWS

                                          PIPE SIZE (INCHES)           FLOW (GPM)
                                                   10                       500

                                                   12                       750

                                                   14                       960

                                                   16                      1,250

                                                   18                      1,400

                                                   20                      1,800

                                                   24                      2,500



23.13    CLOSED SYSTEMS WATER TREATMENT

         23.13.1          CHEMICAL FEEDERS



Issued January 31, 2009                                                                               23 00 00 27/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          A.   Provide building closed loop systems with a filter chemical bypass feeder, with
                               flow indicator. Install the filter bypass feeder across the pump to allow for a
                               minimum five (5) psi pressure drop. Connect the discharge side of the pump to
                               the top of the feeder and the suction side of the pump to the bottom.
         23.13.2          PLANT CHILLED WATER AND CONDENSER WATER TREATMENT
                          A.   The Contractor shall utilize TCCD’s water treatment company to maintain the
                               chemical treatment and provide monthly test reports to TCCD and to the
                               contractor through the FB to verify proper chemical treatment and testing of the
                               water. TCCD’s water treatment company will provide all chemicals required for
                               the condenser and chilled water systems. This comprehensive Water Treatment
                               Service shall meet the following objectives: Provide a cost-effective program to
                               keep systems clean and corrosion free. Provide multi-directional
                               communications, training, measurements, and quality. Provide a high sense of
                               urgency and professionalism. Maintain corrosion and microbiological rates
                               within specifications. Provide safe and error-free deliveries. Minimize all health
                               risks to building occupants and those in the surrounding communities,
                               particularly in relation to Legion Ella Pneumophila. Minimize the impact on local
                               environmental resources, including water consumption and the environmental
                               impact of tower discharge. Maximize the operating efficiency of the systems.
                               Prevent unscheduled down time for the critical systems and to minimize
                               downtime for all other systems.
                          B.   Contractor shall provide on-site service calls as needed, or within three (3)
                               hours of notification in event of an emergency. At a minimum, sixteen (16) calls
                               per year will be provided per facility and at least one (1) per month. Two (2) site
                               visits per month during height of cooling season. A written service report shall
                               be discussed with site personnel prior to leaving the site. An emailed copy shall
                               be sent to all persons on that site’s correspondence list within 48 hours.
                          C.   A computer generated service report must be provided to all designated
                               personnel at the end of each service visit and should include:
                               1.   Conditions found.
                               2.   Chemical inventory level.
                               3.   Cycles of concentration.
                               4.   PPM of chemical actively in system for each active.
                               5.   Recommended readings, changes, additions, etc.
                               6.   Verification of mineral balances including calcium, ortho-phosphate, m-
                                    alkalinity, iron & copper).
                               7. Recommended actions needed and follow-up plan.
                          D.   All heat exchange surfaces must be kept free of deposition, biological growth,
                               and pitting.
                          E.   CONTROL SYSTEM: The control system should be designed to provide
                               conductivity control, inhibiter feed, dual biocide feed and corrosion coupon
                               monitoring. The control system should be mounted onto a brushed stainless
                               steel panel and include but not be limited to the following components and
                               functions:
                               1.   Treatment Station to include at a minimum a coupon rack with two (2)
                                    stations (clear) to monitor copper and steel losses. Add a third for Stainless
                                    monitoring should that metal be present in the cooling tower assembly.
                               2.   System to include electronic water conductivity monitoring.
                               3.   System to include flow meter.


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               4.   Station back to be made of brushed stainless steel or appropriate plastic or
                                    composite material to support the controller, coupon rack, and mounted
                                    pumps. Station back material to be approved by the FB. Pumps cannot rest
                                    on top of chemical drums.
                               5. Controller allows for remote dial up and system status, monitored by
                                    vendor.
                               6. Electronic chemical drum level monitoring required.
                               7. Isolation valves required at both the entry and exit points of the system to
                                    allow for component changes without disruption to the condenser loop.
                               8. Modbus connection to BAS required for connection to station controller.
                                    Software to be loaded for on and off-site monitoring.
                               9. Controller to allow for chemical feed lock out during blow down cycles.
                               10. Controller to monitor and prevent the feeding of both biocide and inhibitor
                                    simultaneously.
                               11. Chemical feed connections to occur on the station piping via short runs of
                                    poly piping.
                               12. Electronic motorized ball valves on blow down lines.
                               13. The addition of makeup and blow down metering for water consumption
                                    analysis for the HVAC system.
                          F.   Equipment Contractor shall keep the customer informed on the latest
                               technology available in the water treatment industry and help develop and
                               forecast a master plan to upgrade existing equipment.
                          G.   MSDS sheets should accompany all chemicals supplied. All chemicals shall be
                               stored in an EPA and OSHA approved vessel with containment.
                          H.   All biocides used in the program must be registered with the proper agency and
                               all labels must bear the registration number. All biocides must be EPA
                               registered for use in re-circulating water systems and be approved for discharge
                               into surface waters and municipal sewage systems. Biocides must meet all local
                               state and federal requirements.
                          I.   All Chemicals supplied under contract shall be the product of one (1)
                               manufacturer whose primary business is that of producing water treatment
                               chemicals, and shall not cause damage or deterioration of the system’s
                               equipment or materials.
         23.13.3          PLANT CHILLED WATER AND CONDENSER WATER TREATMENT (EXISTING)
                          A.   TCCD Physical Plant Department shall coordinate with the contractor through
                               the FB to provide the services of a company regularly engaged in the treatment
                               of condenser and chilled water systems to determine the correct chemicals, the
                               concentrations required, and the water treatment equipment sizes and flow
                               rates required for the systems being designed. TCCD Physical Plant
                               Department shall specify their water treatment company to maintain the
                               chemical treatment and provide monthly test reports to TCCD and to the
                               contractor through the FB to verify proper chemical treatment and testing of the
                               water. TCCD’s water treatment company will provide all chemicals required for
                               the condenser and chilled water systems. Avoid the use of acid treatment and
                               proprietary chemicals. The chemical representative shall monitor the system
                               water chemistry and provide adjustment as necessary to maintain the system
                               chemistry within the recommended ranges and limits.
                          B.   TCCD Physical Plant and Engineering Department shall coordinate with the
                               contractor through the FB to provide the services of a company regularly
                               engaged in the treatment of condenser and chilled water systems to specify a


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               condenser water treatment system capable of automatically feeding chemicals
                               and bleeding the system to prevent corrosion, scale, and biological formations.
                               Automatic chemical feed systems will automatically feed chemicals into the
                               chilled and condenser water based on varying system conditions. Arrange
                               chemical monitoring controls, metering pumps, and feeder tubing in an orderly
                               arrangement adjacent to the central plant equipment.
                          C.   Continuously monitor the condenser water return conductivity and provide
                               chemical controls and a modulating blow-down discharge to maintain four (4)
                               cycles of concentration in the condenser water system.
         23.13.4          PLANT HOT WATER BOILER CHEMICAL WATER TREATMENT
                          A.   TCCD Physical Plant Department shall coordinate with the contractor through
                               the FB to provide the services of a company regularly engaged in the treatment
                               of boilers and hot water systems to determine the correct chemicals, the
                               concentrations required, and the water treatment equipment sizes and flow
                               rates required for the systems being designed to maintain proper water
                               chemistry. TCCD Physical Plant Department shall specify their water treatment
                               company to maintain the chemical treatment and provide monthly test reports to
                               TCCD and to the contractor through the FB to verify proper chemical treatment
                               and testing of the water. TCCD’s water treatment company will provide all
                               chemicals required for the boilers and hot water systems. Treat the circulating
                               water system to maintain the conditions recommended by the boiler
                               manufacturer. Chemicals shall meet required federal, state, and local
                               environmental regulations for the treatment of boilers, safe for discharge to the
                               sanitary sewer.

23.14    HEATING HOT WATER BOILERS

         23.14.1          GENERAL REQUIREMENTS
                          A.   Provide boiler system installation complete with necessary accessories for
                               operation, and comply with all local, state and federal codes. Boiler construction
                               to comply with ASME Section VIII requirements.
                          B.   Provide lineup of high-efficiency condensing, fully modulating, natural gas-fired,
                               forced draft, packaged fire tube hot water boilers, sized to handle the campus
                               design heating load. Design boilers in a parallel piping arrangement, with
                               efficiency optimized staged operation to respond to the campus heating
                               demand. Provide condensing boiler lineup with N+1 redundancy. Aerco low
                               NOx Benchmark series or approved equal.
                          C.   In addition to the base campus hot water heating system described in 2.13.B,
                               provide one additional UL listed three-pass, fire-tube wetback dual-fuel boiler,
                               with combination burner controls capable of operating using either natural gas
                               or #2 diesel fuel oil. Size boiler for 60% of the campus design heating load
                               expected at full build out. Provide boiler with minimum 6:1 turndown ratio.
                               Hurst series S4-GO-RGL40/2-3LN or approved equal.
                          D.   Refer to Chapter 22 Plumbing for diesel fuel oil storage requirements.
                          E.   Design central plant hot water system piping with automated valve arrangement
                               to allow the use of the condensing boiler lineup and/or the dual-fuel boiler, for
                               operational flexibility.
                          F.   Layout equipment and rooms to allow installation with sufficient clearances for
                               maintenance.
                          G.   Provide boilers with constant volume primary-side circulating pumps.


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          H.   Provide blowdown tank and/or blowdown separator with automatic drain water
                               tempering for boiler system.
                          I.   Specify boiler with efficiencies in accordance with the latest edition of ASHRAE
                               90.1 as accepted by the Texas State Energy Conservation Office (SECO).
                          J.   Specify low NOx boiler with emissions in compliance with the current levels set
                               forth by Texas Commission on Environmental Quality (TCEQ).
                          K.   Provide each boiler with necessary controls interface or datalink to fully
                               integrate with the BAS.
                          L.   Configure distribution layout so that heating water distribution pumps take
                               suction from the boiler outlet connection and pump through the campus load, to
                               decrease the potential for air entry into the system and to reduce the system
                               head on the boiler.
                          M.   Provide inline centrifugal separator in the pump suction line.

23.15    WATER CHILLERS

         23.15.1          GENERAL REQUIREMENTS
                          A.   Evaluate the selection of water-cooled chillers with respect to efficiency based
                               on Life Cycle Cost, to determine the optimum unit selection.
                          B.   Evaluate chiller selections based on three (3) different machine efficiencies:
                               First, the base bid shall be the designed chiller at the highest efficiency
                               available. Alternates shall meet ASHRAE 90.1 minimum requirements at the
                               design operating conditions and shall include the Life Cycle Cost Analysis. See
                               Life Cycle Cost Analysis section for additional information.
                          C.   Evaluate the applicability of an integrated free-cooling heat recovery package
                               for the chiller(s) selected in the first step life cycle cost analysis. If deemed
                               acceptable based on life cycle cost, provide factory free-cooling option on the
                               chiller lineup designed to supply campus cooling requirements during the
                               months of the year when condenser water free cooling is available (i.e. free-
                               cooling may not necessarily be required for every chiller in the system). This
                               needs to be compared with providing the appropriate flat plate heat exchanger.
                          D.   Evaluate the applicability of a heat-recovery chiller for incorporation into the
                               central plant mechanical design, based on ASHRAE 90.1 conformance and
                               economic justification based on life cycle cost analysis. Consider the total
                               campus heat, cooling and reheat loads, and the duration of each based on the
                               energy analysis.
                          E.   Provide factory-assembled and tested, packaged water cooled, liquid chiller
                               consisting of (VFD with adaptive internal controls(if applicable to specific
                               design)), centrifugal compressor, compressor motor, condenser, evaporator,
                               purge unit, refrigeration accessories, instrument and control panel including
                               gauges and indicating lights, auxiliary components and accessories, and motor
                               starters. Smaller facilities may utilize air cooled screw chillers. Provide units
                               meeting the requirements of ARI Standard 550/590. Trane or approved equal.
                          F.   Evaporator and Condenser: Provide flanged piping connections, with marine
                               water boxes for both evaporator and condensers, with thermometer well for
                               temperature controller, thermometer well and thermometer, nipple and flow
                               switch, tee and valve for pressure gauge on the inlet connection. On the outlet,
                               provide thermometer well for temperature controller, thermometer well and
                               thermometer, tee and valve for pressure gauge.



Issued January 31, 2009                                                                           23 00 00 31/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          G.   Provide extended factory warranty for parts, labor, and refrigerant for a period of
                               ten (10) years from date of start up. Warranty shall include factory authorized
                               preventative maintenance program consisting of one (1) annual inspection and
                               three (3) run inspections. (Provide factory authorized preventative maintenance
                               scope of work).
                          H.   Provide chillers with single point electrical connections to vendor-provided
                               remote starters mounted adjacent to the chiller unit.
                          I.   Do not specify VFD motor controls on 4160 volt chillers.
                          J.   Provide each chiller with necessary controls interface or datalink to fully
                               integrate with the Campus Facility Management Control System (BAS).
                          K.   Comply with ASHRAE 15 (latest edition) for construction and operation of
                               refrigerant systems related to centrifugal chiller installations.
                          L.   Allow sufficient clear space equal to the overall length and width of the machine
                               for tube pull clearance inside the mechanical room.
                          M.   Provide factory closed-cell foam insulation for chiller cold surfaces.

23.16    AUTOMATIC TUBE BRUSHING

         23.16.1          GENERAL INFORMATION: An Automatic Tube Brushing (ATB) System shall be
                          installed on each air conditioning water cooled chiller condenser (absorber and
                          condenser on absorption machines) to provide optimum tube cleanliness and heat
                          transfer. The systems are to be manufactured and installed by Water Technology of
                          Pensacola, Inc., Pensacola, Florida.
         23.16.2          PRODUCT DISCRIPTION: The ATB System automatically maintains tube fouling at
                          or below design conditions without interrupting normal equipment operation. The ATB
                          System consists of special nylon brush inserted in each tube and a catch basket
                          attached to each end of the tube. A special four-way valve is installed to permit
                          reversing the direction of water flow. The brush is caught in the opposite end basket
                          and remains there until flow is reversed again, thus repeating the process. The
                          frequency of the reversing cycle is set up to match job conditions (normally twice per
                          eight (8) hours). The four-way valve’s pneumatic or electric actuator is controlled by a
                          pre-set time cycle that assures regular tube brushing during equipment operation.
         23.16.3          EQUIPMENT SPECIFICAITON:
                          A.   TURBO BRUSH AND BASKET SETS: One (1) set per each condenser tube.
                               1.   Turbo Brush (one (1) per set): Each brush to be nylon bristle, titanium wire
                                    and polypropylene tips. One (1) tip to have vanes to cause increased
                                    spiraling of brush through tubes for superior cleaning. Brush to have
                                    interference fit with ID of tube not to exceed 0.025” interference.
                               2.   Basket (two (2) per set): Low pressure drop design, polypropylene basket
                                    with removable 4-prong end-clip; neck outside diameter to press fit inner
                                    diameter of tube. End-Clip shall not restrict basket end more than 25%.
                                    Basket shall allow for removal and replacement of brushes from tubes.
                               3.   Epoxy for Basket Installation: Special two-part water-proof epoxy for basket
                                    installation to have similar co-efficient of expansion as tube material.
                               4.   Provide 5% spares of brushes and basket sets per chiller.
                          B.   FOUR-WAY VALVE: Valve shall be Water Technology’s Standard HX Valve
                               and shall be of steel construction (A36 or better) positive sealing type, with all
                               internal sealing parts of hard rubber and 304 Stainless Steel. Valve shall have
                               parallel flow connections to minimize field installation piping and labor. Valve


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               shall be plug type to allow for field adjustment of plug-to-seat clearance to
                               minimize bypass. It shall be manufactured in accordance with ASME Unfired
                               Pressure Vessel Code Specification per Section VIII for operation at a system
                               working pressure of 125 PSIG with a maximum differential of 35 PSIG. End
                               connections shall be flanged, victaulic or plain or welding. Valve shall be
                               hydrostatically tested to 1.5 times the designed working pressure. Valve shall
                               allow for manual fail-safe turning, and have a mechanical position indicator.
                          C.   PNEUMATIC ACTUATOR: To be pre-mounted on the valve. Double actuating
                               cylinder to assure trouble-free operation. Operation to be on 50 to 100 PSIG air
                               pressure supplied by customer.
                          D.   POSITION CONTROL SWITCHES: Micro-switch to be supplied for valve to
                               indicate complete turn of valve in normal and reverse flow.
                          E.   CONTROL PANEL: The on-load control shall have the following features:
                               1. NEMA 4X enclosure with mounting bracket.
                               2. Cycle counter.
                               3. 24-hour timer to automatically initiate the on-load cleaning cycle.
                               4. Manual Override of pre-set cleaning cycle.
                               5. Power On Light.
                               6. Diverter Position Indicator Lights:
                                  a. Normal Flow.
                                  b. Reverse Flow.
                               7. Malfunction Light – To indicate slow turning or incomplete valve turning.
                               8. 4-Way Solenoid Valve for actuator operation to be mounted at control panel
                                  or actuator.
                               9. OPTIONAL as required for reliable operation:
                                  a. Flow Switch Bypass.
                                  b. Electric Chiller Unloading.
                          F.   OPERATION AND INSTALLATION MANUAL: Two (2) Copies to be provided.
                          G.   SHOP TESTING: In addition to test specified for the valve, Manufacturer will
                               functionally test the entire system prior to shipment including valve, actuator,
                               solenoid valve, position indicator and control panel.
                          H.   FIELD SUPERVISION: Manufacturer shall supply field supervision of brush and
                               basket installation to assure proper installation and to protect manufacturer’s
                               warranty.
                          I.   FIELD SERVICE AND REPLACEMENT PARTS: Manufacturer will maintain at
                               all times an adequate inventory of replacement parts that are available for
                               immediate shipment. Qualified field service personnel shall be available from
                               manufacturer (at added cost) on short notice to service or repair equipment
                               furnished.
                          J.   WARRANTY: Manufacturer shall guarantee system, when operated according
                               to its instructions, and shall provide a fouling factor in the condenser of .00025
                               or better. Manufacturer to warranty components for one (1) year against
                               defective materials and workmanship. Defective parts to be returned freight
                               prepaid to factory and will be replaced FOB from manufacturer’s plant.
                          K.   MANUFACTURER: The ATB System is manufactured by:
                                    Water Technology of Pensacola, Inc.
                                    3000 W. Nine Mile Road


Issued January 31, 2009                                                                            23 00 00 33/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                    Pensacola, Florida 32534
                                    TEL: 850-477-4789
                                         800-282-7978
                                         800-ATB-SYST
                                    FAX: 850-479-3056

23.17    COOLING TOWERS

         23.17.1          GENERAL REQUIREMENTS
                          A.   Evaluate the selection of a cooling tower (packaged stainless steel or field
                               erected masonry-shell) based on life cycle cost, to determine the optimum
                               selection for the system. Refer to the Life Cycle Cost Analysis section for
                               additional information. Select cooling tower to optimize overall plant kW/ton.
                          B.   Coordinate the cooling tower selection with the Design Professional and the FB
                               to meet project specific requirements for acoustic performance, aesthetics,
                               plume discharge, etc. Account for site-specific cooling tower requirements in
                               Life Cycle Cost evaluation.
                          C.   Select cooling towers with a design condenser water supply temperature of
                               85ºF, with a ten (10) degree temperature differential based on an 80ºF wet bulb
                               temperature as a minimum capacity/sizing.
                          D.   Design cooling towers to support the application of a chiller free-cooling system,
                               if applicable.
                          E.   Use submersible stainless steel hot water coils for cooling tower basin freeze
                               protection from plant heating system.
                          F.   Provide cooling tower with vibration limit switch mounted on fan assembly to
                               automatically shutdown fan operation on excessive vibration.
                          G.   Connect condenser water piping to tower using flanged inlet and outlet
                               connections.
                          H.   Connect makeup water piping with flanged or union connections to tower. Heat
                               trace exterior makeup water piping.
                          I.   Connect overflow and drains to the sanitary sewer system with a code-approved
                               connection.
                          J.   Provide safety railings, and ladder and safety cage from bottom of tower to
                               access fan deck, fabricated of stainless steel or fiberglass, per OSHA
                               requirements.
                          K.   Design cooling towers to operate using variable-frequency driven fans staged to
                               modulate based on the BAS optimization programming. Where multiple cells are
                               in operation, control fan VFD speeds equally between operating cells. The
                               motors specified shall be premium efficiency rated for use with VFD operation
                               with intended application. The motors shall be located outside the air stream.
                               Coordinate with BAS provider for Condenser Water optimization requirements.
                          L.   Provide condenser water system with packaged side stream media filtration skid
                               sized to filter the contents of the entire condenser water system volume
                               contents a minimum of once every hour.
                          M.   Coordinate cooling tower finish/screening        requirements    (e.g.   aesthetic
                               treatment, screen wall, etc.) with the FB.




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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          N.   Specify cooling towers to be tested upon installation completion in accordance
                               with the requirements of CTI-ATC-105, Acceptance Test Code for Water
                               Cooling Towers.
                          O.   Coordinate cooling tower fire protection requirements with local Fire Marshall,
                               and/or provide FM® Approved cooling tower in lieu of required sprinkler
                               protection. Evaluate fire protection requirements and required maintenance in
                               life cycle cost evaluation.
                          P.   Design cooling towers with operational flexibility to accommodate use with
                               chiller free-cooling heat exchangers.
                          Q.   Ensure gearbox lubrications systems are designed to provide adequate
                               lubricant circulation when operating with variable frequency drives and minimum
                               speeds.
         23.17.2          FIELD ERECTED MASONRY COOLING TOWERS
                          A.   Provide field erected masonry (as identified by the Life Cycle Cost analysis)
                               cooling tower utilizing a counter-flow induced draft design, including replaceable
                               PVC fill bundles, PVC drift eliminators, FRP venturi-type fan shroud, PVC hot
                               water distribution piping system with spray nozzles and a gear-driven polyester
                               or glass-reinforced epoxy propeller fan assembly with VFD duty motor and
                               splash-lubricated speed reducer gearbox assembly, with oil level and fill lines
                               extending outside the fan shroud.
                          B.   Provide field-erected masonry tower with nominal eight-inch thick concrete
                               exterior walls and interior cell partitions and a cast-in place concrete fan deck.
                               Coordinate exterior aesthetic requirements (brick, aggregate finish, etc.) with
                               Design Professional.
                          C.   Design field-erected cooling towers to be installed on top of a concrete water
                               basin. Coordinate water basin design with Design Professional.
                          D.   Provide cooling tower with full-size return water bypass connection from the cell
                               return piping to the cold water basin for cold-weather operation to bypass the
                               cooling tower fill.
         23.17.3          PACKAGED STAINLESS STEEL COOLING TOWERS
                          A.   Packaged cooling towers, provide complete factory assembled unit or units for
                               outdoor installation, cross-flow induced draft type vertical discharge tower with
                               gear-drive axial fan, water distribution basins, and VFD compatible premium
                               efficiency motor. Unit to be constructed entirely of type 304 stainless steel with
                               14 mil thick PVC fill.
                          B.   Provide packaged cooling tower with self-cleaning, stainless steel collection
                               basin with bottom outlet.
                          C.   Provide inlet screens in front of fill to eliminate debris from being drawn into the
                               tower, and bottom mounted sump outlet connection with drain.
                          D.   Provide fan assembly with VFD duty motor, splash-lubricated speed reducer
                               gearbox assembly and one-piece, removable welded stainless steel wire fan
                               guard. Provide axial flow fan selected to meet the acoustic requirements of the
                               site installation.
                          E.   Provide packaged cooling towers with equalization header pipe to maintain
                               equal basin water levels on headered cooling tower cells.
                          F.   Provide cooling tower with full-size return water bypass connection from the cell
                               return piping to the cold water basin for cold-weather operation to bypass the
                               cooling tower fill.

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          G.   Provide five (5) year warranty for watertight assembly of cold water basin and
                               against failure of any mechanical equipment component of the fan driven
                               system and its supports, with the exception of the motor. Include repair or
                               replacement of defective materials in the warranty.

23.18    HEAT EXCHANGERS

         23.18.1          GENERAL REQUIREMENTS
                          A.   When required, provide plate and frame heat exchangers for chilled water and
                               hot water service fabricated using 304 stainless steel plates, EPDM gaskets,
                               rated and labeled for minimum 200 psig operating pressure.
                          B.   Provide shell-and-tube heat exchanger for pool heating applications. Select heat
                               exchanger sizing to be the greater of either maintaining an 88oF pool
                               temperature with 110oF water entering the heat exchanger from central plant or
                               sized for a 30-hour warm-up at a 20oF pool temperature rise from 68 to 88oF
                               plus standing losses with 140oF entering water temperature from the central
                               plant. Coordinate with the FB for final design selection.

23.19    AIR DISTRIBUTION SYSTEMS

         23.19.1          GENERAL REQUIREMENTS
                          A.   Provide central station air handling units configured to serve campus buildings
                               or portions of buildings consistent with good engineering practice and zoned in a
                               practical manner to facilitate convenient building operation and shutdown.
                               Provide Life Cycle Cost Analysis as appropriate to differentiate between air
                               handling system types and unit sizes in order to determine the optimal system
                               configuration. Coordinate with the FB for final equipment selections.
                          B.   Utilize dedicated 100% outside air handling units to pre-treat ventilation air prior
                               to delivery to main central air handling units. Provide outside air handling units
                               dedicated to a single or group of central air handlers consistent with prudent
                               engineering practice and to facilitate convenient building operation and
                               shutdown.
                          C.   Design building air distribution systems using factory fabricated air handling
                               units with fan, fan motor, filtered mixing boxes, damper sections, filter section,
                               guards, belt drives, chilled water and hot water coil section and other
                               accessories. Unit shall be constructed of a complete structural frame with
                               removable panels. Unit manufacturer shall ship separate segments so unit can
                               be broken down for ease of installation in tight spaces. The entire air handler
                               shall be constructed of galvanized steel. Casing finished meeting ASTMB 117
                               250-hour salt-spray test. For units with completely mig-welded tubular steel
                               frame and base all external parts of the unit shall be thoroughly cleaned and
                               painted with a prime coat and the factory standard color.
                          D.   Air handling units to be installed in interior mechanical rooms. Design
                               mechanical rooms to provide adequate maintenance clearances for service for
                               coil pull, fan and fan shaft removal, filter service, etc. Show required service
                               clearances using dashed lines on the Drawings.
                          E.   Provide vibration isolation curbs (Mason Industries model RSC or approved
                               equal) sized to match the air handling unit base rail for air handler installations
                               on floors above grade if air handlers are not internally isolated.
                          F.   Provide electronic enthalpy controlled economizer in accordance with ASHRAE
                               90.1 for air handling unit systems, to serve design airflow requirements using
                               100% outside air. Economizer operation to be controlled by the BAS for

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               individual air handling units to maintain space temperature and humidity
                               conditions.
                          G.   Control air handling system outside air supply rates using a carbon-dioxide
                               based demand ventilation control strategy in conjunction with monitoring
                               occupancy in critical rooms to reduce the total supply of outside air during
                               periods of reduced occupancy. Monitor the carbon-dioxide levels in the zones
                               or systems as well as the outdoor levels, and vary ventilation rates to track a
                               carbon dioxide offset consistent with ASHRAE 62 recommendations.
                          H.   Provide safety controls in air handling units along with sequences of operation in
                               the BAS to protect water coils from damage due to freezing.
                          I.   Acceptable Manufacturers:
                               1.   CES Group
                               2.   McQuay
                               3.   Trane
                               4.   Others only on a case by case basis after approval by the FB.
         23.19.2          CENTRAL AIR HANDLING UNITS
                          A.   CONSTRUCTION:
                               1.   Provide double wall casing construction with two (2) inch thick, three (3)
                                    pound per cubic foot density neoprene coated glass fiber insulation.
                                    Provide double-die formed 18 gauge unit casing with galvanized exterior
                                    panels, installed with closed cell neoprene gaskets. Specify with panels
                                    that are completely removable without affecting structural integrity of unit.
                                    Provide solid inner liner panels of galvanized steel. Provide thermal break
                                    construction between exterior panel and frame to ensure an airtight fit.
                               2.   Provide double wall access door panels with full perimeter gaskets. Provide
                                    with door handles operable from both the exterior and interior of the unit.
                                    Door hardware shall be surface mounted to minimize penetrations in the
                                    door casing that could lead to air leakage paths. Access panels and doors
                                    shall be fully removable without the use of specialized tools to allow
                                    complete access of all interior surfaces. Provide a minimum of one (1)
                                    access door for each fan, filter, and access section. Door height to be full
                                    height of unit wall panel or maximum of 72 inches tall. Service access with
                                    hinged access door required between coils to insure complete access to fin
                                    surfaces and drain pan for cleanablity. Coils mounted back-to-back in coil
                                    sections will not be considered as system IAQ is compromised.
                               3.   Provide one (1) piece drain pans constructed from Type 304 stainless steel
                                    with insulation between pan and casing. Drain pan shall have raised lips,
                                    welded corners, and pipe drain connection. Cross break and double slope
                                    pan, and pitch to drain connection. Provide drain pans extending under
                                    complete cooling coil section and hot water coil section. Provide drain pans
                                    extending a minimum of 24 inches downstream of cooling coils or as
                                    recommended by manufacture for moisture carry over but no less than six
                                    (6) inches. Provide downspouts and intermediate condensate collectors for
                                    cooling coil banks greater than one (1) coil high shall be same material as
                                    base unit drain pan.
                               4.   Construct coil section so coils can be removed without affecting the
                                    structural integrity of the casing. Completely enclose connections, coil
                                    headers, and return bends. Do not use coil frame as structural member for
                                    coil section. Provide stainless steel cooling coil casings with galvanized
                                    supporting frame work.


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               5.   Provide each access section with a 100-watt equivalent compact
                                    fluorescent lamp in a vapor tight marine light with sealed glass fixture and
                                    metal guard. Provide weatherproof switch located on the unit exterior near
                                    the fan access door.
                               6.   Provide UV-C disinfectant systems downstream of coils.
                               7.   Unit as shipped from the factory shall be ARI-430 certified. If the specific
                                    project requirements can only be met by a custom unit, then manufacturer
                                    shall provide performance testing in accordance with ARI standard testing
                                    procedures. The recommended testing procedure shall be submitted to the
                                    DP and the FB for review. The FB at its option will determine whether the
                                    testing procedure will be witnessed by a TCCD representative.
                               8.   Unit as shipped from the factory shall conform to UL 1995 Standard and be
                                    listed in either UL/CUL or ETL directory. Units shall be provided with listing
                                    agency label affixed to unit. In the event the unit is not UL/CUL or ETL
                                    approved, the contractor shall, at his/her expense provide for a field
                                    inspection by a UL/CUL or ETL representative to verify conformance. If
                                    necessary, contractor shall perform modifications to the unit to comply with
                                    UL/CUL or ETL as directed by the representative, at no additional expense
                                    to the owner.
                          B.   FANS, MOTORS, AND DRIVE ASSEMBLIES
                               1.   Provide fans of type and class as specified on the schedule. Fan shafts
                                    shall be solid, coated with a rust-inhibiting coating, and properly designed
                                    so that fan shaft does not pass through first critical speed as unit comes up
                                    to rated RPM. All fans shall be statically and dynamically tested by the
                                    manufacturer for vibration and alignment as an assembly at the operating
                                    RPM to meet design specifications. Fans controlled by variable frequency
                                    drives shall be statically and dynamically tested for vibration and alignment
                                    at speeds between 25% and 100% of design RPM. If fans are not factory-
                                    tested for vibration and alignment, the contractor shall be responsible for
                                    cost and labor associated with field balancing and certified vibration
                                    performance. Fan wheels shall be keyed to fan shafts to prevent slipping.
                               2.   Provide heavy-duty pillow block or flange type, self-aligning,
                                    grease-lubricated ABMA 9 bearings, with an L-50 life of 200,000 hours.
                                    Provide with lubrication lines extended to exterior of fan casing with Zerk
                                    fitting rigidly attached to casing. Provide lubrication fittings on side of unit
                                    away from mechanical room wall.
                               3.   Provide ASTM A-108 steel shafts, grade 1040/1045, precision turned, and
                                    ground and polished. The shaft's first critical speed shall be at least 120%
                                    of the fan's maximum operating speed. Provide shaft with counter-sunk
                                    drive end for tachometer readings. Hollow shafts are not acceptable.
                               4.   Provide open drip proof, NEMA premium efficiency motors with inverter
                                    grade insulation to meet NEMA MG-1 Part 31 Class F, NEMA Design B
                                    performance, with double shielding bearings. Select non-overloading
                                    motors at all points on the RPM operating curve.
                               5.   Provide fixed sheave for motors equipped with VFD. Provide matched belts
                                    and drive rated for minimum one and one-half times nameplate rating of
                                    motor. Provide a minimum of two (2) belts on all fans ten (10) horsepower
                                    and larger.
                               6.   Mount motor and fan assembly, and fan on integral isolated framework.
                                    Mount framework on vibration isolators on casing interior. Factory
                                    mounted motor on slide base that can be slid out the side of the unit if
                                    removal is required. Provide internal flexible connection on fan discharge
                                    to isolate fan from casing. For units with external spring isolation curb

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                    assemblies, provide internal fan isolation lockouts to prevent dynamic
                                    frequency interferences during operation.
                          C.   COILS
                               1.   Provide coil section with coils and allow access to both sides of coils. Fully
                                    enclose coil headers and return bends within the casing. Slide coils into
                                    casing via removable end panel with blank off sheets and sealing collars at
                                    connection penetrations. Extend coil connections a minimum of five (5)
                                    inches beyond unit casing.
                               2.   Provide counterflow water coils, six (6) rows deep for chilled water entering
                                    45ºF and leaving 62ºF and up to six (6) rows deep for heating hot water
                                    entering 140ºF and leaving 100ºF, to meet or exceed specified design
                                    loads for sensible and total capacity requirements. Provide an additional
                                    coil bank if additional cooling capacity is needed. Allow access between
                                    coil banks for cleaning and service.
                               3.   Rate coils in accordance with ARI certified data. Select coil to provide
                                    capacity in accordance with water flow and temperatures with maximum
                                    water pressure drop through coil of 15 feet and maximum velocity in tubes
                                    of five (5) feet per second. Maximum face velocity for chilled water coils not
                                    to exceed water carryover limit at design conditions.
                               4.   Provide coils constructed of 5/8 inch outside diameter copper tubes, with
                                    aluminum plate fins, maximum ten (10) fins per inch, and copper headers.
                                    Provide coils with plate fin wall thickness and tubes wall thickness to
                                    standard of coil type and tube diameter by coil manufacture. Provide with
                                    minimum 16 gauge Type 304 stainless steel casing. Coils to be suitable for
                                    250 psig and up to 300ºF operating conditions.
                               5.   Provide equal hydraulic resistance paths where there is more than one coil
                                    or more than one coil connection to and from a single pressure
                                    independent characterized control valve (PICCV).
                               6.   Select coil to maintain leaving water temperature at 100%, 75% and 50% of
                                    design load.
                          D.   FILTERS
                               1.   Filter housings to be manufactured by the air handling unit manufacturer.
                                    Provide access doors on each side of section. Provide gasketed
                                    galvanized steel filter blanks to prevent air bypass around filters. Filter
                                    arrangement to flat with a maximum of 450 feet per minute across filter
                                    area.
                               2.   Provide main filter sections to accommodate four (4) inch deep pleated,
                                    MERV 8, (ASHRAE 52.2) filters for main air handling units. Provide in
                                    same filter section appropriate fastened adaptor to accommodate two (2)
                                    inch pleated MERV 8 filters. Consider higher MERV ratings to enhance
                                    indoor air quality per LEED initiatives. Coordinate with FB.
                               3.   Provide pre-filter section to accommodate four (4) inch pleated, MERV 8,
                                    (ASHRAE 52.2) pre-filters. Provide in same section appropriate fastened
                                    adapter to accommodate two (2) inch pleated MERV 8 pre-filters. Provide
                                    odor control filter section to accommodate two (2) inch MERV 7 activated
                                    carbon filters. Provide final filter section to accommodate twelve (12) inch
                                    HEPA filters with appropriate fastened adapter in this section to
                                    accommodate two (2) inch pleated MERV 8 filters for final filters. This
                                    filtering is required on dedicated outside air handlers.
                               4.   Provide each filter bank with a Magnehelic (Dwyer Series 2000) differential
                                    air pressure gage with static pressure tips. Gage to be mounted on the
                                    exterior unit casing.

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               5.   Air cleaner shall be electronically enhanced polarized media air cleaner. Air
                                    cleaner shall have an active electrostatic field that will not ionize airborne
                                    particles or produce ozone. Air cleaner shall at a minimum have a prefilter
                                    rated at 25-30% per ASHRAE 52.1(MERV 6-7 per ASHRAE 52.2). Air
                                    cleaner shall be tested and meet CSA Standard 22.2 No. 187-M19986 and
                                    UL Standard 867 for electrostatic filters.
                          E.   DAMPERS
                               1.   Provide low leakage dampers with extruded aluminum airfoil blades, flat or
                                    formed metal blades are not acceptable. Provide internally mounted ultra
                                    low leak airfoil blade dampers as scheduled on drawings. Dampers shall
                                    be Ruskin CD60 or equivalent. Construct damper blades and damper
                                    frames of galvanized steel, with metal compressible jamb seals and
                                    extruded vinyl blade edge seals. Blades shall rotate on stainless steel
                                    sleeve bearings. Damper blade lengths shall not exceed 60 inches Damper
                                    leakage rates shall not exceed 4 cfm per square foot at 1” water gage in
                                    compliance with ASHRAE 90.1.
                          F.   ENERGY WHEELS WITH ARI 1060
                               1.   The air-handling unit shall have a total energy wheel capable of both latent
                                    and sensible heat energy exchange, as an integral part of the air-handling
                                    unit. Only rotary wheels that are ARI 1060 listed shall be considered.
                                    Wheel performance shall meet or exceed scheduled performance, but shall
                                    be no less than 70% effective when the specified flow rate and exhaust
                                    rate are equal. On mixed air units, the return air damper shall be an
                                    integral part of the energy wheel section. Access sections with service
                                    doors shall be provided both upstream and downstream of energy wheel.
                                    Access shall be of sufficient length in direction of airflow to provide physical
                                    access to both airstreams paths for periodic wheel maintenance or
                                    cleaning. Energy recovery system shall have both certified performances of
                                    the air-handling unit (ARI 430 and ARI 410) and of the enthalpy wheel.
                                    (ARI 1060).
                          G.   DEHUMIDIFICATION OPTION
                               1.   The desiccant dehumidification wheel shall be placed in the air handler as
                                    shown in the air handler unit drawings. The dehumidification wheel shall
                                    not require an additional regeneration airflow stream or the use of a high
                                    heat source. If any preheat is required it shall not exceed the scheduled
                                    capacity.
                               2.   The desiccant dehumidification wheel shall not utilize exhaust air. The
                                    desiccant wheel shall have no exhaust air transfer.
                               3.   Cassettes can be designed with either a vertical (side by side) or a
                                    horizontal (over/under) airflow arrangement as per requirements. The
                                    cassette shall be mounted upright.
                               4.   Cassette casing shall be constructed of heavy duty G90 galvanized steel.
                                    Cassettes up to 7000 cfm shall be single face panel construction for easy
                                    service access to the wheel drive motor and belt. Larger cassettes shall be
                                    double face panel with removable side panel for access to belt and drive
                                    motor. Small amounts of casing deflection shall have no significant impact
                                    on wheel performance or life. Casings shall have a 1”-1 1/2" perimeter
                                    flange to facilitate mounting inside AHU cabinet with self-tapping sheet
                                    metal screws. Alternatively, cassettes may be mounted using “safeoff”
                                    blanking to the side, top, and bottom of the cassette.
                               5.   The desiccant dehumidification wheels shall be constructed of synthetic
                                    matrix with an adsorbent integrally bound into the matrix. The adsorbent

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                              shall be selected for its high affinity for water vapor at the desiccant
                              operating conditions. The adsorbent shall be a type III desiccant.
                              Construction of the wheel shall be corrugated, fluted design, which
                              provides distinct air passageways and prevents internal wheel bypass. The
                              desiccant is intimately, permanently bound and uniformly dispersed
                              throughout the wheel matrix. Because the desiccant is not applied as a
                              glued on surface coating, it is not susceptible to erosion, abrasion, or
                              delamination of the desiccant. The wheel matrix shall be rigid and glued
                              layer-to-layer, and not susceptible to sagging or separation of the layers.
                              The wheel shall be structurally reinforced with a spoking system to
                              minimize wheel deflection. Because the product is nonmetallic, it offers
                              complete resistance to corrosion. The media shall meet the flammability
                              requirements governing this class of products and be UL recognized
                              components in accordance to UL 1812 and UL1995.
                          6. All cassettes shall include both a circumferential seal as an air block-off
                              around the perimeter, and an inner diametric seal separating regeneration
                              and supply sides. Seals shall be full contact nylon brush seals, which
                              minimizes leakage. Seals are factory set and field adjustable and make
                              intimate contact with the wheel on all surfaces. DESICCANT cassette,
                              wheel and seal configuration allows for operation at high differential
                              pressures. Seal replacement should not be necessary during the life of the
                              product.
                          7. The drive system shall consist of a heavy-duty fractional horsepower A/C
                              gear motor mounted in the cassette and cooled by the AHU air stream.
                              Motor location shall be as required. All motors have permanently lubricated
                              bearings. Minimal amp draw will be required and all motors shall be
                              115V/1PH/60Hz or 230V/1PH/60Hz. Drive belts shall be high performance
                              v-belt multilink belts. The multilink belt allows for replacement of individual
                              links(1” each) if a section of belt becomes worn or breaks. Belts are
                              installed under tension, require no mechanical tensioner, and do not
                              require adjustment after startup. The rotation speed of the wheel shall not
                              exceed the scheduled value.
                          8. The wheel matrix shall be cleanable by vacuuming or pressurized air
                              blowing, or alternatively with low temperature steam, hot water, light
                              detergent.
                          9. Cassettes shall be provided with bearings which support rotation of the
                              wheel around a center shaft driven by a perimeter belt. The bearings shall
                              be internal ball bearings press fitted into the bored wheel hub for all wheels
                              up to and including 72” diameter. Internal bearings are permanently
                              lubricated, no maintenance bearings which support fixed shaft operation of
                              the wheel assembly. Flanged or pillow block bearings which support
                              rotating shaft operation of the wheel assembly are used for all units larger
                              than 72” diameter. Outboard bearings are provided with grease fittings for
                              periodic lubrication. L10 bearing life is greater than 400,000 hours at
                              design conditions.
                          10. The wheel cassette shall be capable of continuous operation over ambient
                              temperatures ranging from -40ºF to 200ºF at any relative humidity without
                              adversely affecting wheel performance or life.
                          11. Performance shall be as predicted by DESICCANT selection software as
                              scheduled. The performance shall be based on testing conducted on the
                              wheel cassette installed in the air handler configuration as shown in the
                              AHU drawings. Performance based on stand-alone desiccant wheel
                              cassette or tests with two (2) independent air streams are unacceptable.
                              Performance data shall be from tests of a complete unit per-formed by an


Issued January 31, 2009                                                                        23 00 00 41/49
TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                   ISO 9000 certified laboratory. Temperature measurements shall be taken
                                   using instrumentation whose calibration is traceable to NIST standards.
                                   Dry bulb and wet bulb temperature measurements shall be accurate to +/-
                                   0.1ºF. Performance prediction for the DESICCANT air handler shall be
                                   available for multiple conditions as required.
                               12. WARRANTY: The dehumidification wheel shall be warranted for a period
                                   of five (5) years from date of manufacture (terms and conditions apply).
                                   The warranty applies to all parts and components in the cassettes with the
                                   exception of the motor, which is warranted for a period of eighteen (18)
                                   months.
                          H.   UV-C LIGHTS FOR HVAC EQUIPMENT
                               1.   UV-C lights shall be factory engineered to provide no less than 200
                                    microwatts per square centimeter of UV-C energy, at no more than 13
                                    watts of power consumption per each square foot of treated, cross
                                    sectional area. Acceptable UV-C light suppliers shall be Ultraviolet
                                    Devices, Inc. Other suppliers shall be considered, but must be approved by
                                    the engineer prior to bidding.
                               2.   UV-C lamps shall be positioned downstream of the cooling coil and shall
                                    irradiate the leaving air side of the cooling coil and the condensate drain
                                    pan.
                               3.   UV-C lights shall be positioned so as to provide equal distribution of energy
                                    as specified in section 2.07A while minimizing shadowing. Each lamp shall
                                    contain no more than 5 milligrams of mercury and shall be capable of
                                    operating in ambient temperature from 55 - 135ºF. Lamp life shall be 9000
                                    hours minimum, with no more than 20% loss of output after one (1) year of
                                    continuous operation.
                               4.   All fixtures shall be functionally tested after factory installation by the air
                                    handling unit manufacturer. Fixtures shall be recognized by UL/C-UL under
                                    Category Code ABQK (Accessories, Air Duct Mounted), UL Standards:
                                    153, 1598 & 1995 respectively.
                               5.   All polymeric materials that are exposed to UV-C light must either be tested
                                    or certified as UV-C tolerant or must be shielded from direct or reflective
                                    light using UV-C tolerant material, such as metal. UV-C tolerant shall be
                                    defined as capable of performing intended duty for the twenty (20) year
                                    design life of the air handler.
                               6.   A dedicated external light switch shall be installed to disconnect power from
                                    the UV-C lights. Switch shall include lockout/tagout capabilities and shall
                                    be installed within visual sight of the lights. All points of access to sections
                                    where UV-C lights are located must have a mechanical interlock switch
                                    wired to disconnect power to the lights if a door is opened or the primary
                                    access panel is removed. A viewing window shall be provided to allow for
                                    full view of the UV-C array as a means of confirming proper operation.
                                    Viewing window shall be treated and tested to insure that any energy
                                    transmitted through the window is below the threshold limits as specified by
                                    NIOSH and ACGIH.
                               7.   UV-C bulbs shall ship with the air handling unit to the job site, and shall be
                                    appropriately packaged to prevent breakage in shipment. Each shipment
                                    shall include a Material Data Safety Sheet (MSDS). Unit manufacturer’s
                                    installation and maintenance manual shall contain information relating to,
                                    but not limited to, safety, maintenance, and servicing instructions for UV-C
                                    lights and fixtures.
         23.19.3          DUCTWORK


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          A.   GENERAL REQUIREMENTS
                               1.  Fabricate, support, and seal in accordance with SMACNA HVAC Duct
                                   Construction Standards – Metal and Flexible and ASHRAE Handbook
                                   Fundamentals and ASHRAE Handbook HVAC Systems and Equipment.
                                   Provide duct material, gages, and reinforcement for scheduled system
                                   operating pressures.
                               2. Structurally design supply and return ductwork for minimum of 2” WG
                                   positive and negative internal pressures with minimum G90 galvanized
                                   steel coatings. Utilize low static pressures to maintain energy efficiencies
                                   and provide low noise generation.
                               3. Seal ductwork to SMACNA seal Class A.
                               4. Provide balancing dampers at supply, return, and exhaust branches when
                                   connected to larger ducts, as required for air balancing.
                               5. Connect diffusers to low pressure ducts with a five (5) foot maximum length
                                   of flexible duct. Hold in place with strap or clamp.
                               6. Clean duct system and force air at high velocity through duct to remove
                                   accumulated dust. To obtain sufficient air, clean half the system at a time.
                                   Protect equipment that may be harmed by excessive dirt with temporary
                                   filters, or bypass during cleaning.
                               7. FIBERGLASS DUCT BOARD IS NOT ALLOWED.
                               8. FLEXIBLE DUCTS: Interlocking spiral fabricated of galvanized steel or
                                   aluminum construction, or fabric supported by helically wound spring steel
                                   wire or flat steel bands; rated to 2 inches WG positive and 1-1/2 inches WG
                                   negative.
                               9. INSULATED FLEXIBLE DUCTS: Flexible duct, wrapped with minimum
                                   one (1) inch thick flexible glass fiber insulation, enclosed by seamless
                                   aluminum pigmented plastic vapor barrier jacket; maximum 0.23 "k" value
                                   at 75 ºF.
                               10. Provide flexible duct hanger supports at four feet on center. Maximum sag
                                   not to exceed 1/2-inch per foot.
         23.19.4          DUCTWORK ACCESSORIES
                          A.   FLEXIBLE DUCT CONNECTORS: UL listed fire-retardant neoprene coated
                               woven glass fiber fabric to NFPA 90A, minimum density 20 ounce per square
                               yard, approximately six (6) inches wide, crimped into metal edging strip.
                               Provide electrical bonding jumpers across flexible connection. Fabricate per
                               SMACNA HVAC Duct Construction Standards – Metal and Flexible.
                               1.   Provide flexible duct connection on all rotating equipment.
                          B.   ACCESS DOORS: Provide hinged access doors conforming to SMACNA HVAC
                               Duct Construction Standards in ductwork where indicated and at all air flow
                               measuring stations, automatic dampers, fire dampers, coils, thermostats, and
                               other apparatus requiring service and inspection in the duct system. Provide
                               access doors upstream and downstream of air flow measuring stations, duct
                               heaters and coils. Equip doors 24 x 24 inches or larger with fasteners operable
                               from inside and outside the duct. Use insulated type doors in insulated ducts.
                               1.   Coordinate access      door   requirements   and    locations   with   Design
                                    Professional.
                          C.   FIRE AND COMBINATION FIRE/SMOKE DAMPERS:
                               1.   Fabricate in accordance with NFPA 90A and UL 555 for dynamic closure
                                    under flow and pressure for designed systems and as indicated.


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               2.   Install fire dampers in accordance with their UL listing.
                               3.   Provide frames large enough to eliminate obstruction to airflow when the
                                    damper is open.
                               4.   Coordinate combination fire/smoke damper installation with Design
                                    Professionals for power and fire alarm connections.
                               5.   Coordinate access to concealed fire and fire/smoke dampers with Design
                                    Professional. Provide access door in ductwork for replacement of fusible
                                    links and damper-related accessories. Demonstrate damper access to
                                    satisfaction of TCCD Physical Plant and Engineering Offices through the
                                    FB.
                          D.   DAMPERS:
                               1.   VOLUME CONTROL DAMPERS: Fabricate per SMACNA HVAC Duct
                                    Construction Standards – Metal and Flexible. Operate manual volume
                                    control dampers by locking-type quadrant operators. Provide dampers two
                                    (2) gauges heavier than the duct in which installed, using opposed blade
                                    type with maximum blade width of twelve (12) inches. Provide access
                                    doors or panels for all concealed damper operators and locking setscrews.
                                    Provide with stand-off mounting brackets, bases, or adapters to provide
                                    clearance between the duct surface and the operator not less than the
                                    thickness of the insulation when installed on insulated ductwork.
                               2.   GRAVITY BACKDRAFT DAMPERS: Fabricate multi-blade, parallel action
                                    gravity balanced backdraft dampers of 16 gage galvanized steel, with
                                    center pivoted blades of maximum six (6) inch width, with felt or flexible
                                    vinyl sealed edges, linked together in rattle-free manner with 90-degree
                                    stop, steel ball bearings, and plated steel pivot pin; adjustment device to
                                    permit setting for varying differential static pressure.
                               3.   CONTROL DAMPERS: Fabricate control damper with airfoil-shaped,
                                    single-piece, multi-blade with edge type low leakage blade seals, parallel
                                    action control dampers of heavy duty 6063-T5 extruded aluminum, with a
                                    maximum width of four (4) inches, with horizontal orientation and linkage
                                    concealed in frame. Provide minimum 1/2-inch diameter plated steel, hex-
                                    shaped axles, mechanically attached to blades. Provide molded synthetic
                                    sleeve bearings, turning in hole on frame. Provide flexible metal
                                    compression type jamb seals. Maximum 3.5 cubic feet per minute per
                                    square foot leakage at one (1) inch water gage for all sizes 24 inches wide
                                    and above with a maximum pressure drop of 0.05-inch water gage at 1,500
                                    feet per minute across a 24-inch by 24-inch damper.
         23.19.5          AIR INLETS AND OUTLETS
                          A.   DIFFUSERS, REGISTERS, AND GRILLES: Factory-fabricated of steel or
                               aluminum and designed to distribute the specified quantity of air evenly over
                               space intended without causing noticeable drafts, air movement faster than 50
                               fpm in occupied zones, or dead spots anywhere in the conditioned area. Outlets
                               for diffusion, spread, throw, and noise level shall be as required for specified
                               performance. Performance shall be certified according to ASHRAE 70. Provide
                               sound rated and certified inlets and outlets according to ASHRAE 70. Provide
                               opposed blade type diffusers and registers provided with volume damper with
                               accessible operator. Provide volume dampers for all diffusers and registers,
                               except linear slot diffusers. Provide linear slot diffusers with round or elliptical
                               balancing dampers. Protect inlet and outlet openings that are located less than
                               seven (7) feet above the floor using a grille or screen according to NFPA 90A.
                          B.   Provide ceiling diffusers with four way air pattern controllers.



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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          C.   Provide double deflection supply registers with individually adjustable vertical
                               and horizontal blades.
                          D.   Fabricate air inlets and outlets from galvanized steel or aluminum sheets with
                               galvanized or aluminum structural shapes. Conform to SMACNA HVAC Duct
                               Construction Standards Sheet metal thickness, reinforcement, and fabrication
                               shall. Provide exterior air inlets and outlets with bird screens conforming to
                               ASTM E 2016, No. 2 mesh, aluminum or stainless steel.
         23.19.6          FANS
                          A.   Specify fans tested and rated according to AMCA 210.
                          B.   Specify fan sound power levels not to exceed 85 dB(A) when tested per AMCA
                               300 and rated per AMCA 301. All fans to carry an AMCA Seal.
                          C.   Connect fans to the motors either directly or indirectly with V-belt drive. Use V-
                               belt drives designed for not less than 120 % of the connected driving capacity.
                               Provide variable pitch sheaves for motors 15 hp and below. Select variable pitch
                               sheaves to drive the fan at a speed to produce the specified capacity when set
                               at the approximate midpoint of the sheave adjustment. When fixed pitch
                               sheaves are furnished, provide a replaceable sheave when needed to achieve
                               system air balance. Provide motors for V-belt drives with adjustable rails or
                               bases. Provide removable metal guards for exposed V-belt drives, and provide
                               speed-test openings at the center of rotating shafts. Provide fans with personnel
                               screens or guards on both suction and supply ends, except that screens are not
                               required, unless otherwise indicated, when ducts are connected to the fan.
                          D.   Specify fans with L50 bearing life rated at not less than 200,000 hours as
                               defined by ABMA 9 and ABMA 11.
                          E.   Provide fan and motor assemblies with vibration-isolation supports or
                               mountings. Use vibration-isolation units that are standard products with
                               published loading ratings.
         23.19.7          AIR TERMINAL UNITS
                          A.   Provide variable volume, single duct terminal units with a calibrated air volume
                               sensing device, air valve or damper, actuator, and accessory relays. Select
                               units capable of controlling air volume to within +/-5% of each air set point
                               volume, as determined by the zone thermostat demand with variations in inlet
                               pressures from one-tenth to six (6) inches water gauge. Specify units with
                               internal resistance not to exceed four-tenths of an inch water gauge at
                               maximum flow range. Provide external differential pressure taps separate from
                               the control pressure taps for airflow measurement with a zero to one inch water
                               gauge range. Select units with a maximum inlet velocity of 1500 feet per minute.
                               Provide unit with a factory-mounted 24 volt transformer for single point electrical
                               connection. Provide 25% spare flow capacity in VAV terminal units for potential
                               changes in space use. Select units that have factory integrated and calibrated
                               BAS controller from vendor that supplies TCCD BAS. Fan powered units shall
                               be equipped with high efficiency ECM motors. Other air terminal units shall be
                               considered on a case by case basis. Coordinate with the FB for final design
                               selections.
                          B.   Select units with enclosures constructed of minimum 18 gauge galvanized steel.
                               Factory set unit air volume and ensure unit accommodates field adjustment
                               without special tools. Attach a flow chart to each unit. Base acoustic
                               performance of the terminal units upon units tested according to ARI 880 and
                               ANSI/ASHRAE Standard 130. Select units so that discharge and radiated sound
                               power levels do exceed a Noise Criteria NC-30. Display discharge sound power
                               shall be shown for minimum and 1-1/2 inches water gauge inlet static pressure.

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               Provide 3/4” internal lining with all edges sealed against airflow erosion in
                               accordance with NFPA 90A and UL 181. Specify units with maximum casing
                               leakage not to exceed 2% at three (3) inches water gauge, closed damper
                               leakage not to exceed 2% at three (3) inches water gauge.
                          C.   Select fin-and-tube type hot-water reheat coils constructed of seamless copper
                               tubes with aluminum fins mechanically bonded to the tubes and copper
                               headers. Specify 16 gauge casing and tube support sheets fabricated of
                               galvanized steel, formed to provide structural strength. Select drainable coils
                               conforming to ARI 410, suitable for 250 psig working pressure, with circuited
                               tubes for proper water velocity without excessive pressure drop. Factory test
                               each coil at not less than 300 psig air pressure.
         23.19.8          SPECIAL VENTILATION SYSTEMS
                          A.   VEHICLE EXHAUST SYSTEMS: Coordinate with specific project requirements.
                               1.   Design system in accordance with SMACNA Accepted Industry Practice for
                                    Industrial Duct Construction, SMACNA Rectangular Industrial Duct
                                    Construction Standards, SMACNA Round Industrial Duct Construction
                                    Standards, ASHRAE Handbook – HVAC Applications, American
                                    Conference of Governmental Industrial Hygienist (ACGIH) Manuals, as
                                    required.
                          B.   LABORATORY VENTILATION SYSTEMS: Coordinate with specific project
                               requirements.
                               1.   Design system in accordance with SMACNA HVAC Systems Applications,
                                    SMACNA Accepted Industry Practice for Industrial Duct Construction,
                                    SMACNA Rectangular Industrial Duct Construction Standards, SMACNA
                                    Round Industrial Duct Construction Standards, ASHRAE Handbook –
                                    HVAC Applications, US OSHA 29 CFR Part 1910, NFPA 45, ANSI/AIHA
                                    Z9.5, American Conference of Governmental Industrial Hygienist (ACGIH)
                                    Manuals, and National Institute of Health (NIH) design guidelines, as
                                    required.
                          C.   SHOP VENTILATION           SYSTEMS:      Coordinate    with   specific   project
                               requirements.
                               1.   Design system in accordance with SMACNA Accepted Industry Practice for
                                    Industrial Duct Construction, SMACNA Rectangular Industrial Duct
                                    Construction Standards, SMACNA Round Industrial Duct Construction
                                    Standards, ASHRAE Handbook – HVAC Applications, American
                                    Conference of Governmental Industrial Hygienist (ACGIH) Manuals, as
                                    required.
                          D.   KITCHEN VENTILATION AND EXHAUST SYSTEMS: Coordinate with specific
                               project requirements.
                               1.   Design Systems in accordance with SMACNA HVAC Systems
                                    Applications, ASHRAE Standard 154P, ASHRAE Handbook – HVAC
                                    Applications, NFPA Standard 96, UL Standard 300, UL Standard 710, UL
                                    Standard 762.

23.20    TESTING, ADJUSTING, AND BALANCING

         23.20.1          GENERAL REQUIREMENTS
                          A.   TCCD furnished testing, adjusting, and balancing (TAB) services for HVAC,
                               piping, ductwork and plumbing systems will be provided in accordance with
                               Associated Air Balance Council (AABC) Standards, National Environmental

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                               Balancing Bureau (NEBB) Standards, or SMACNA TAB Standards. TAB
                               services contractor shall report directly to the FB.
                          B.   All recommendations and suggested practices contained in the selected TAB
                               Standard are considered mandatory. Use the provisions of the selected TAB
                               Standard, including checklists, report forms, procedures, etc.
                          C.   Provide a complete set of Drawings and Specifications to the FB TAB firm at
                               Schematic Design, Design Development and Construction Document review
                               milestones. Adequately address TAB firm comments to satisfaction of the FB.

23.21    LIFE CYCLE COST ANALYSIS

         23.21.1          GENERAL REQUIREMENTS
                          A.   Perform a life cycle cost analysis (LCCA) for identified mechanical equipment
                               and systems to evaluate the relevant costs associated with system operation
                               and performance over a specified service life. The LCCA evaluates relevant
                               costs, including design, procurement, installation, operation, system life,
                               maintenance, repair, replacement, salvage, utility cost escalation, interest and
                               depreciation, among other factors, over a specified study period to determine
                               the option that offers the lowest cost over the life of the system in terms of that
                               option’s present value.
                          B.   Perform an LCCA for the identified systems and equipment using a procedure
                               consistent with ASTM E 917, Standard Practice for Measuring Life-Cycle Costs
                               of Buildings and Building Systems. Commercially available software may be
                               used for the analysis, including BLCC5 (Building Life Cycle Cost), a program
                               developed by the Office of Applied Economics at the National Institute of
                               Standards and Technology. The software is available for download through the
                               U.S. Department of Energy (DOE) Federal Energy Management Program
                               (FEMP) website at http://www.eere.energy.gov/femp/program/lifecycle.cfm.
                          C.   Perform the LCCA based on a present value analysis. If using the BLCC5
                               program, utilize the End of Year Discounting method with the Constant Dollar
                               Analysis (simplified to omit inflation influence, as utility cost escalations are
                               accounted for elsewhere in the program).
                          D.   The following inputs and economic parameters are required to complete the
                               LCCA. Current economic data should be obtained from the FB to the fullest
                               extent possible prior to evaluation. Use consistent economic factors throughout
                               LCCA evaluations to avoid disparity between analyzed alternatives.
                               1.   REAL DISCOUNT RATE (time value of money).
                               2.   EQUIPMENT/SYSTEM SERVICE DATE: Set the period of analysis to
                                    equal the expected life of the system. Use equipment life data appropriate
                                    for the expected usage and system installation. ASHRAE-Applications
                                    Handbook data tabulated in Estimates of Service Lives of Various System
                                    Components may be used for consistency.
                          E.   COST DATA:
                               1.   INITIAL CAPITAL COST: Compile a comprehensive and accurate cost
                                    estimate of the expected design, procurement and installation cost for the
                                    proposed system or equipment to be evaluated. Use cost data sources
                                    such as R.S. Means Cost Data books (current year) or estimates
                                    generated by a contractor or cost estimator for system cost input. Use
                                    consistent cost data sources between analyzed alternatives.
                               2.   ANNUAL OPERATING COST: Operating costs should be determined
                                    based on the electricity, natural gas and water utility rates provided by the

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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                                   FB. Apply utility rates to annual system energy consumption and
                                   performance simulations, performed in accordance with ASHRAE 90.1 of
                                   this Standard, to determine the operating costs for each alternative.
                               3. Use the same operational system profile for evaluation of alternatives.
                               4. Escalate annual utility rates per the FB.
                               5. ANNUAL MAINTENANCE COST: Estimate annualized maintenance costs
                                   for each system or piece of equipment to be evaluated. Use maintenance
                                   cost data provided by the FB or estimate maintenance costs using the
                                   procedure outlined in the Owning and Operating Costs chapter of the
                                   ASHRAE-Applications Handbook.
                                   a. SALVAGE VALUE: Assess salvage or resale value to systems or
                                         equipment as appropriate.
                                   b. Omit from the LCCA costs that are not significantly affected by system
                                         selections or design decisions between alternatives.
                                   c. When one analyzed alternative offers an opportunity to avoid Capital
                                         Costs by reducing building or system scope in other areas of design
                                         (e.g. one system alternative eliminates the need for building square
                                         footage required by another alternative), reduce the Capital Cost of
                                         that particular alternative by the amount of the avoided capital
                                         expense.
                                   d. Cash flows should be simplified to occur at the end of the year for
                                         evaluation purposes.
                               6. In the event any of the required economic data not available through
                                   TCCD, use the data provided in the DOE FEMP Annual Supplement to
                                   Handbook 135 (ASHB 135), Energy Price Indices and Discount Factors for
                                   Life-Cycle Cost Analysis.
                               7. When performance advantages exist that favor one alternative over
                                   another (e.g. one system offers superior comfort, or improved noise
                                   performance over another), make adjustments to incorporate the
                                   differences into the LCCA by subtracting the value of the performance
                                   improvement from the corresponding cost of the alternative. Coordinate
                                   with the FB for evaluation of qualitative issues.
                               8. The system or equipment alternative providing the lowest Life Cycle Cost
                                   should be selected as the best alternative, assuming the proposed
                                   alternative is capable of satisfying the design and operating requirements.
                               9. Refer to ASTM E 917 and NIST Handbook 135, Life Cycle Costing Manual
                                   for the Federal Energy Management Program, for specific guidance on
                                   completing the LCCA.
                               10. Provide a list of assumptions and inputs to the FB for review and approval
                                   prior to completion of the Life Cycle Cost Analysis.
                          F.   Provide an LCCA to determine the optimal equipment selections and system
                               alternatives including but not limited to the mechanical equipment and systems
                               listed below:
                               1.   Optimized chiller selection and piping configurations with respect to
                                    performance.
                               2.   Applicability of VFD compressors for selected central plant chillers.
                               3.   Applicability of integrated chiller free-cooling module for selected chillers.
                               4.   Applicability of heat recovery chiller to serve campus loads.
                               5.   Applicability of Thermal Energy storage (stratified CHW) for campus chilled
                                    water system.


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TARRANT COUNTY COLLEGE DISTRICT DESIGN STANDARDS
DIVISION 23 – MECHANICAL


                          6.   Field erected versus packaged stainless steel cooling towers.
                          7.   Building envelope upgrades exceeding ASHRAE 90.1 requirements by
                               30%.
                          8.   Other alternatives as identified by the FB.


                                          END OF DIVISION




Issued January 31, 2009                                                            23 00 00 49/49

				
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Description: hvac design and selection methods