Docstoc

Specification Smardt water Cooled Chillers Smardt Chiller Group

Document Sample
Specification Smardt water Cooled Chillers Smardt Chiller Group Powered By Docstoc
					Guide Specification – Smardt Water Cooled Chillers

PART 1 — GENERAL
1.1 SUMMARY
Section includes design, performance criteria, refrigerants, controls, and installation requirements for water-
cooled centrifugal chillers.

1.2 REFERENCES
Comply with the following codes and standards:
ARI 550/590 NEC
ANSI/ASHRAE 15
ASME Section VIII
ETL Listed
ANSI UL 1995
CSA C22.2 No. 236

1.3 SUBMITTALS
Submittals shall include the following:
A. Dimensioned plan and elevation drawings, including required service clearances and location of all field piping
and electrical connections.
B. Summaries of electrical and water utility requirements during operation.
C. Control system diagram showing points for field interface and connection to external BMS systems. Drawings
shall show field and factory wiring.
D. Installation and Operating Manuals.

1.4 QUALITY ASSURANCE
A. Regulatory Requirements: Comply with the standards in Section 1.2.

1.5 DELIVERY AND HANDLING
A. Chillers shall be delivered to the job site completely assembled.
B. Comply with the manufacturer’s instructions for transporting and rigging.

1.6 WARRANTY and MAINTENANCE
A. The chiller manufacturer’s warranty shall be for a period of one year from date of equipment start up or 18
months from the date of shipment, whichever occurs first.
B. The warranty shall include parts costs for the repair or replacement of parts found to be defective in material or
workmanship.
C. Maintenance of the chiller equipment shall be the responsibility of the owner.

PART 2 — PRODUCTS

2.1 ACCEPTABLE MANUFACTURERS
A. Smardt,Inc.
B. Approved Equal

2.2 PRODUCT DESCRIPTION
A. Provide and install as shown on the plans a factory assembled water-cooled packaged chiller.
B. Each unit shall include one or more Turbocor, oil-free, magnetic bearing, and variable-speed centrifugal
compressors. Integrated variable frequency drive shall operate with inlet guide vanes to optimize part load
efficiency. Chillers shall operate with HCF-134a refrigerant not subject to phase-out by the Montreal Protocol and
the U.S. Clean Air Act.
C. The evaporator, condenser, and expansion valve shall be configured to operate as one refrigerant circuit. The
chiller unit compressors shall be designed for mechanical and electrical isolation to facilitate service and removal.

2.3 DESIGN REQUIREMENTS
A. Provide a complete water-cooled, TurboCor compressor equipped chiller as specified. Unit shall consist of one
or more magnetic bearing, oil-free centrifugal compressors with integrated variable frequency drive, refrigerant
evaporator, condenser and operating controls with equipment protection.
B. Performance: Refer to schedule on the set of project drawings. When utilizing Turbocor model TT300
compressors (90 nominal tons), the chiller shall be capable of stable operation to 15% percent of full load with
one compressor chillers and less than 15TR of full load capacity with two or more compressors with standard ARI
entering condenser water temperature and without utilizing hot gas bypass. When utilizing Turbocor model TT400
compressors (140 nominal tons), the chiller shall be capable of stable operation to 40% percent of full load with
one compressor chillers and less than 40TR of full load capacity with two or more compressors with standard ARI
entering condenser water temperature and without utilizing hot gas bypass.
C. Acoustics: Sound pressure for the unit shall not exceed 72 dBa at three feet and shall represent the highest
levels recorded at all load points. Sound data shall be measured according to ARI Standard 575-87.
D. Chiller shall be equipped for single-point power connection.

2.4 CHILLER COMPONENTS
A. Compressors:
1. Compressors shall be of hermetic centrifugal design and operate 100% oil-free with two two-stages of
compression, magnetic bearings, and integrated variable frequency drive system.
2. Automatically positioned and controlled inlet guide vanes shall operate with compressor speed controls to
provide optimum unit efficiency and stable operation at part loads.
3. The compressor shall be capable of coming to a controlled stop in the event of a power failure. The unit shall
be capable of initializing an automatic restart in the case of power failure.

B. Refrigerant Evaporator and Condenser:
1. Evaporator and condenser shall be shell-and-tube type and have separate shells. Heat exchangers shall be
designed, constructed, tested and stamped according to the requirements of the ASME Code, Section VIII. In
both the evaporator and condenser, refrigerant shall be in the shell and water inside the tubes. The water sides
shall be designed for a minimum of 150 psig or as specified. Vents and drains shall be provided. The refrigerant
side of each vessel shall bear the ASME Code stamp. Vessels shall pass a test pressure of 1.1 times the working
pressure but not less than 100 psig. Provide intermediate tube supports spaced to enable equal liquid and gas
flow across multiple compressor suction ports.
2. The evaporator shall be provided with spring loaded reseating-type pressure relief valves according to
ASHRAE-15. The condenser shall be provided with dual relief valves equipped with a transfer valve so one valve
can be removed for testing or replacement without loss of refrigerant or removal of refrigerant from the vessel.
Rupture disks are not acceptable.
3. A perforated plate designed for vapor disengagement shall be installed inside the evaporator above the tubing
to assure effective liquid droplet removal to prevent liquid damage to compressors and equalized suction pressure
across evaporators with multiple compressors.
4. Tubes shall be individually replaceable and have internally and externally enhanced surfaces designed for
refrigeration duty. Tubes shall have smooth full tube wall landings at the tube-sheet ends and at intermediate tube
supports. Tubes shall be mechanically roller expanded into steel tube sheets containing a minimum of three
concentric grooves.
5. Minimum evaporator exiting water temperature shall be 38°F. Minimum entering condenser water temperature
shall be 55°F. Minimum inlet condenser water to outlet chilled water difference shall be 12°F.

C. Liquid level controls
1. Control of refrigerant flow shall utilize a 6,000 step electronic expansion valve, EXV, to operate within the full
range from full load to the lowest loading capacity for the chiller. Fixed orifice metering devices or float controls
using hot gas bypass are not acceptable. The EXV liquid line shall sight glass with moisture indicator.
3. Condenser shall be equipped with a mechanical stainless steel float for electronic actuation of the EXV to
provide a positive liquid seal to assure effective cooling of the compressor.

C. Prime Mover:
1. Permanent-magnet, synchronous hermetically sealed motor of sufficient size to effectively provide compressor
horsepower requirements. Motor shall include soft-start capabilities with an inrush current of no more than 2
amps. Motor shall be liquid refrigerant cooled with internal thermal overload protection devices embedded in the
winding of each phase.
2. Compressor motor and chiller unit shall include variable-frequency speed controls to match cooling load
demand to compressor speed and inlet guide vane position.
3. Each compressor shall be equipped with a line reactor.

D. Chiller Controls
The Kiltech controller fitted to the Smardt oil-free centrifugal chiller package shall be an
embedded real time microprocessor device that utilizes control software written specifically for
Smardt chiller applications. User operation shall be accomplished using a panel mounted color
touch-screen interface. The status of the compressors and all system parameters including
compressor alarms and temperature trends shall be viewable.

D1. Chiller control system shall have the capability to store one year of operational data. No less
than 60 points of information shall be sampled at a maximum of 15 minute intervals.

D2. Chiller control system shall have full web based remote control capability including the
capability for remote operation and software updates.

Controller Features shall include the following:
    Selectable entering, leaving water control or saturated suction temperature
    10.4 inch, 65,000 colors, touch panel operator interface.
    Energy optimization fuzzy logic control of multiple compressors.
    Integrated condensing temperature relief algorithm that controls tower fan and condenser
        pump speed to reduce compressor energy requirements in low ambient conditions.
    Multiple compressor staging algorithm shall operate at the optimized power curves of
        each compressor simultaneously and shall reset automatically every second during
        operation. Compressor staging methods that operates using simple incremental percent
        of demand shall not be accepted.
    Continuous data logging for operational trending and bin analysis shall be exportable to
        “CSV” format. (12 months data stored).
    Standard communications via ModBUS RTU. Multiple communication protocols available
        as options LonTalk FT10, BacNet MSTP, Modbus TCP/IP.
    Embedded Web and FTP servers to enable remote encrypted control, log download,
        software version upload and operational monitoring.
    Full plant control functions – Condenser fan VFD and condenser water pump VFD inputs
        and outputs. VFD chilled water control is optional.
    Built-in stepper motor controls for EXVs
    Controls lockup protection
    Ramp rate control - Peak energy demand limiting algorithms.
    Three levels of alarm safety for minimum chiller down time
    View up to 32,000 alarm and fault events stored with date / time stamp.
    Real time data trending viewable via Touch panel.
    Built in electronic expansion valve controller.
    Chiller load profile charts viewable via Touch panel.

Inputs and Outputs
     Thermistor Inputs (10K NTC) – Qty. 8
     Digital Inputs (Voltage Free) - Qty. 8
     Analogue Inputs (4-20mA or 0-10V) – Qty. 8
     Digital Outputs (Relay) – Qty. 8
     Analogue Outputs (0-10VDC) – Qty. 6
     EXV Output – Bipolar Stepper Motor Drive

Data on Main Display Screen:
       Entering and leaving chilled water temperature.
       Entering and leaving condenser water temperature (if optioned & water-cooled).
       Outside air temperature (if optioned & air-cooled).
       System demand %
       Actual loading
       Chiller set point
       Condenser VFD %
       Total chiller kW
       Total chiller Amp
       Two pages of data trends
       Current alarms (announce and manual reset provision)

2.4. OPTIONAL ITEMS
The following optional items shall be furnished:
1. Marine water boxes
2. Epoxy-coating of inside surfaces of water boxes and tube sheets
3. Aluminum sheet metal protective covering on heat exchangers
4. 0.025 in. tube wall thickness
5. Water side vessel design for of 300 psi operation (150 psi is standard)
6. Single insulation, 3/4 inch, on evaporator, water boxes, suction piping, and compressor end-bell
7. BMS interface module for the interface with BacNET MSTP or LonTalk FT10. ModBUS RTU is standard.
8. Export crating with vapor barrier.
9. 5-year compressor part warranty
10. 5-year compressor parts
11. Extended chiller parts and labor warranty
12. Multiple point power connection, single point is standard
13. EMI filters installed for each compressor
14. Load balancing valves for capacity control
15. Vibration isolation pads
16. Lower leaving chilled water temperatures to 24°F
17. Increased condenser water temperature for heat recovery to 125°F
18. Low profile designs with staggered evaporator and condenser
19. Parallel modular chiller designs for constant of variable flow requirements

PART 3 — EXECUTION

3.1 INSTALLATION
A. Install per manufacturer’s IOM documentation, shop drawings, and submittal documents.
B. Align chiller on foundations or mounting rails as specified on drawings.
C. Arrange piping to enable dismantling and permit head removal for tube cleaning.
D. Coordinate electrical installation with electrical contractor.
E. Coordinate controls and BMS interface with controls contractor.
F. Provide all material required for a fully operational and functional chiller.

3.2 START-UP
A. Units shall be field charged with HFC-134a refrigerant.
B. Factory Start-Up Services: Provide factory supervised start-up on-site for a minimum of two working days
ensure proper operation of the equipment. During the period of start-up, the factory authorized technician shall
instruct the owner’s representative in proper care and operation of the equipment.

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:6
posted:5/5/2013
language:English
pages:4