at-sb by stariya

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									      EVAPCO AT INDUCED DRAFT COUNTERFLOW COOLING TOWER WITH
                        STAINLESS STEEL BASIN

Part 1 General

1.01    Cooling Tower

        Furnish and install as indicated on drawings and schedules, and by requirements
        of this section, (1) packaged induced draft counterflow cooling tower. Crossflow
        type towers shall not be acceptable.

1.02    Codes and Standards

 A.     CTI Compliance: Provide capacity ratings for cooling tower in accordance with
        CTI Certification Standard CTI-201.

 B.     UL and NEMA Compliance: Provide electrical motors and electrical components
        required as part of the cooling tower, which have been listed and labeled by UL,
        and comply with NEMA standards.

 C.     NEC Compliance: Install cooling towers in accordance with NFPA 70.

1.03    Warranty

        The entire structure shall be covered by a five year manufacturer's warranty
        including belt(s), bearing(s), fan(s), fan shaft(s), drive sheave(s), gear box,
        flexible coupling(s), driveshaft(s), and fan motor(s).

Part 2 Product

2.01    Acceptable Manufacturers

        Evapco AT or approved equal.

2.02    Manufactured Units

        Provide units for outdoor use, factory assembled, sectional, counterflow
        industrial duty cooling tower, with sump, fan, surface sections, drift eliminators,
        and motor situated as shown in plans. Each cell shall be CTI certified to cool
        ____ GPM of water from 95ºF to 85ºF at 80ºF EWB. Overall tower dimensions
        shall not exceed: ___ L x ___ W x ___ H. Operating weight shall not exceed
        _____ lbs.

2.03    Mechanical Equipment

 A.     Fan Motor

        Totally enclosed air over (TEAO) or totally enclosed fan cooled (TEFC), 460 volt,
        3 phase, 60 cycle ball bearing fan motor(s) with 1.15 service factor shall be
        furnished suitable for cooling tower service. Motor(s) shall be accessible from
        the outside of the unit for service. Horsepower shall not exceed ___ HP per cell.
B.   Axial Propeller Fans

     Fans shall be heavy duty axial propeller type statically balanced. The fans shall
     be fabricated by the cooling tower manufacturer for single source responsibility
     and reliability. The fans shall be constructed of extruded aluminum alloy blades,
     installed in a closely fitted cowl with venturi air inlet for maximum fan efficiency.
     Each fan blade shall be individually adjustable. Fan cowl shall be covered with a
     heavy gauge hot dip galvanized wire fan guard.

     Optional Low Sound Fan

     Units shall be provided with Low Sound Fan in order to assure a maximum
     sound pressure level of 79 dB measured at 5ft above the fan discharge cylinder
     during full speed operation. Fans shall be high efficiency axial propeller type
     with aluminum wide chord blade construction. Each fan shall be statically
     balanced and installed in a closely fitted cowl with venture air inlet for maximum
     fan efficiency. The fan cowl shall be covered with a heavy gauge hot dipped
     galvanized steel fan guard. There shall be no performance derate when utilizing
     the Low Sound Fan.

C.   Fan Shaft Bearings

     Fan shaft bearings shall be heavy duty self-aligning ball type with grease fittings
     extended to the outside of the unit. Bearings shall be designed for a minimum L-
     10 life of 75,000 hours.

D.   Drive

     The fan drive shall either be belt or gear driven. Belt driven units shall be a
     multigroove, solid back V-belt type with taper lock sheaves designed for 150% of
     the motor nameplate horsepower.           The belt material shall be neoprene
     reinforced with polyester cord and specifically designed for cooling tower service.
     Fan sheave(s) shall be aluminum alloy construction. The fans and fan sheaves
     shall be mounted on the shaft with a specially plated bushing to provide
     maximum corrosion protection. Belt adjustment shall be accomplished from the
     exterior of the unit. Bearing lube lines shall be extended to the exterior of the
     unit for easy maintenance. All sheaves located in the airstream shall be
     constructed of aluminum alloy, vented guards shall be not acceptable. If internal
     belt adjustment is necessary, an internal working platform and ladder is required
     to access the drive system.

     Gear reducers shall be an industrial grade, single-reduction right-angle gear
     reducer with a minimum 2.0 service factor. The gear housing shall be a single
     piece design to eliminate split line seals and assure permanent alignment of
     bearings and gears. All gears shall be precision machined from nickel alloy
     steel, case hardened, and finish ground to class 10 tolerances. Continuous oil
     circulation is assured in either directions of operation or at half speed through the
     location of channels and baffles within the gear casing and the use of an
     oversized slinger on the input shaft. Gear design shall meet or exceed minimum
     applicable AGMA and CTI standards. A gear breather vent is piped to external
     ambient air. The oil fill and drain connections will be extended from the side of
     the gear to the outside of the unit.
2.04   Fill, Louvers and Drift Eliminators

 A.    Fill

        The cooling tower fill shall be PVC (Polyvinyl Chloride) of crossfluted design for
       optimum heat transfer and efficiency. The crossfluted sheets shall be bonded
       together for strength and durability. The fill shall be fabricated, formed, and
       installed by the cooling tower manufacturer and shall be elevated a minimum of
       6" above the floor of the cold water basin to facilitate cleaning. The fill shall be
       suitable for use as a working platform. The PVC fill shall be self-extinguishing
       for fire resistance with a flame spread rating of 5 per ASTM E84-81a. It shall also
       be resistant to rot, decay, or biological attack. The fill shall be able to withstand
       a water temperature of 130ºF.

 B.    Air Inlet Louver Screens

       The air inlet louver screens shall be constructed from polyvinyl chloride (PVC)
       and mounted in easily removable Stainless Steel frames on all four sides of the
       cooling tower for access to the entire basin area for maintenance. The
       removable louvers shall have a minimum of two changes in air direction to
       prevent splashout, block direct sunlight from entering the basin, and shall have
       either a maximum 3/4" opening or stainless steel inlet screens to prevent debris
       from entering the basin.

 C.    Drift Eliminators

       The eliminators shall be constructed entirely of inert polyvinyl chloride (PVC) in
       easily handled sections and be completely separate from the fill section for
       maximum efficiency. The eliminator design shall incorporate three changes in
       air direction to assure complete removal of all entrained moisture from the
       discharge air stream. Maximum drift rate shall be less than 0.001% of the
       circulating water rate.

2.05   Cold Water Basin

       The basin shall be constructed of Type 304 Stainless Steel for long life and
       durability. The basin area shall include all steel components from the base of
       the unit to the top of the air inlet louver screens. Standard basin accessories
       shall include overflow, drain, anti-vortexing hood, Type 304 Stainless Steel
       strainers, and brass make-up valve with plastic float. The entire basin area shall
       incorporate a stepped configuration for reduced water volume, lower operating
       weight and easier basin maintenance. Depressed side outlet sumps which are
       not an integral part of the basin shall not be acceptable. Fiberglass basin liners
       and epoxy coated galvanized support structures will not be acceptable.

2.06   Casing

       The casing shall be constructed of G-235 hot-dip galvanized steel as standard
       for long life and durability. The casing panels shall totally encase the sides of
       the fill section to protect the surface from direct atmospheric contact.

2.07   Water Distribution System
       The spray header and branches shall be constructed of Schedule 40 polyvinyl
       chloride (PVC) pipe for corrosion resistance. The connection to attach the
       external piping shall be galvanized steel. The spray header and branches shall
       be removable for cleaning purposes. The water shall be distributed over the fill
       by precision molded ABS spray nozzles with large 3/8 by 1 inch orifice openings
       and integral sludge ring to eliminate clogging. The nozzles shall be threaded
       into the water distribution piping to assure positive positioning. If open type
       gravity distribution pans are used, they shall include basin covers and both shall
       be constructed of galvanized steel.

2.08   Accessories

 A.    Electric Pan Heaters

       Electric pan heater package consists of electric immersion heaters, heater
       thermostat and low water cutout, all installed in pan. The heaters are sized to
       maintain +40°F pan water temperature with the fans off. Heaters are controlled
       by the thermostat, and the low water cutout prevents the heaters from cycling on
       unless they are completely submerged. Contractor shall provide and field install
       heater contactor, transformer, circuit breaker, disconnect and wiring in conduit
       for complete installation as per manufacturer’s recommendations.

 B.    External Service Platform with Access Ladder

       Cooling towers will be provided with an external service platform with sloped
       aluminum vertical ladder extending to the base of the tower. The platform and
       ladder will allow servicing of the electric motor, fan drive, mechanical equipment
       and water distribution systems.

       On units with gravity type hot water basins, the top of the tower shall also be
       equipped with a sturdy handrail, complete with kneerail and toeboard, designed
       according to OSHA guidelines. An aluminum ladder shall extend from the
       mechanical platform to the top of the perimeter handrail.

 C.    Control Panel

       Each cell shall include a UL listed control panel complete with NEMA 4X
       fiberglass enclosure, single speed fan motor starters, temperature control,
       control voltage transformer, H-O-A switches, and door mounted disconnect
       switch. Panel is to ship loose for field installation by installing contractor.

 D.    Non-Chemical Water Treatment System

       Each cooling tower shall include a non-chemical water treatment system as
       manufactured by Clearwater Systems, Dolphin Series. The Clearwater System
       is to include a coil pipe assembly and transformer panel mounted in NEMA 3R
       panel. The panel shall include a Form C dry contact for remote monitoring.
       System to ship loose for field installation by others.

 E.    Cold Water Basin Sand Filter System

       Each cell shall include sump sweeper piping factory mounted by cooling tower
       manufacturer. Skid mounted filter system to ship loose for field installation and
       connection to factory sump sweeper piping. Skid mounted system shall include
       the following: epoxy coated/lined vessel rated for 100 PSI, automatic air relief
       valve, (2) bronze 3-way control valves, close coupled pump with integral pre-
       strainer, automatic controls with NEMA 3R panel with door disconnect, backwash
       timer, 24 hour backwash clock, differential pressure switch, and electric valve
       actuator. Filter shall have single electrical hook-up point.

 F.    Sentinal Monitoring System

       Cooling tower shall be supplied with Sentinal Monitoring System capable of
       monitoring the following: pan water temperature, water pressure across the
       spray header, pan water conductivity, pan water PH, pan water level, vibration of
       the drive system, fan motor current, and fan motor run time. The monitor and
       alarm panel shall have the following features and capabilities: integrated LCD
       for display of the current status and alarms, front panel LED alarm indicators,
       programmable alarm limits for each measured value, logging of all measured
       values, logging of all alarms, interface to BMS via BACnet MSTP or Modbus
       RTU.

Part 3 Execution

3.01   Installation

 A.    General

       Install cooling tower(s) where indicated in the plans, in accordance with
       equipment manufacturer’s written instructions.

								
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