1.1 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this section.

1.2 SUMMARY:
A. This Section includes factory assembled and tested, closed-circuit forced-draft cooling tower (also known as a closed circuit cooler).

1.3 SUBMITTALS
A. General: Submit the following:
    1. Certified drawings of the closed circuit cooler, sound data, recommended steel support indicating weight loadings, wiring diagrams, installation instructions, operation and maintenance instructions, and thermal performance guarantee by the manufacturer.

1.4 QUALITY ASSURANCE
A. Verification of Performance:
    1. Test and certify closed circuit cooler thermal performance according to CTI Standard 201.
    2. Test and certify closed circuit cooler sound performance according to CTI ATC-128.
B. Meet or Exceed energy efficiency per ASHRAE 90.1.

1.5 WARRANTY
A. Motor/Drive System: Five (5) year comprehensive warranty against materials and workmanship including motor, fan, bearings, mechanical support, sheaves, bushings and belt.
B. Unit: One (1) year from start-up, not to exceed eighteen (18) months from shipment on the unit.

2.1 MANUFACTURERS
A. Manufactures: Subject to compliance with requirements, provide closed circuit cooler manufactured by one of the following:
    1. EVAPCO, Inc.
    2. Approved Substitute

2.2 MATERIALS
A. Galvanized Sheet Steel casing and fan housing complying with ASTM A 653/A 653M and having G-235 designation and Type 304 Stainless Steel basin.
B. Optional Type 304 and/or 316 Stainless Steel as specified.

2.3 FORCED-DRAFT, CLOSED CIRCUIT COOLER
A. Description: Factory assembled and tested, forced draft closed circuit cooler complete with heat transfer coil, fan(s), fan screens, accessories, and rigging supports.
B. Closed Circuit Cooler Characteristics and Capacities: Refer to the Closed Circuit Cooler schedule.
C. Fan(s):
    1. Type and Material: forward curved, centrifugal of hot-dipped galvanized construction. The fans shall be factory installed, and statically and dynamically balanced for vibration free operation.
    2. Fan Housing: The complete drive system, including the electric motor, belts, bearings, fan, and drives shall be completely enclosed in a protective housing which covers the drive system and provides sound reduction.
    3. Maximum sound pressure level of ____dB(A) measured at 5 feet from the fan inlet during full speed operation in accordance with CTI Standard ATC-128.
D. Water Distribution System: Non-corrosive materials.
    1. Evenly distribute of water over heat transfer coil with pressurized spray tree.
        a. Pipes: Schedule 40 PVC, Non-corrosive Materials
        b. Nozzles: Non-clogging, nylon, threaded into branch piping.
    2. Maximum pressure at inlet shall be ____ psig.
E. IBC Compliance: The unit structure shall be designed, analyzed, and constructed in accordance with the latest edition of the International Building Code (IBC) Regulations for seismic loads up to ____ g and wind loads up to ____ psf.
F. Collection Basin Material: Type 304 Stainless Steel or Heavy Gauge G-235 Galvanized Steel (Optional) for long life and durability:
    1. Removable Type 304 Stainless Steel strainer with openings smaller than nozzle orifices.
    2. Joints: Bolted and sealed watertight.
    3. Overflow, Makeup and Drain connections: G-235 Galvanized Steel (MPT and FPT).
G. Casing: Heavy Gauge G-235 Galvanized Steel or Type 304 Stainless Steel (Optional):
    1. Casing panels shall totally encase all sides of the heat transfer surface to protect it from direct exposure to environmental elements. All galvanized steel panel edges shall be coated with a 95% pure zinc compound during fabrication.
    2. Fasteners: Corrosion resistance equal to or better than materials being fastened.
    3. Joints: Sealed watertight.
    4. Welded Connections: Continuous and watertight
H. Heat Transfer Coil: Heavy Gauge G-235 Galvanized Steel encased in a steel framework, assembly hot-dip galvanized after construction. Type 304 Stainless Steel Optional. Coil assembly completely enclosed and protected from sunlight exposure, environmental elements and debris. Tubes sloped for free drainage of the coil and designed for low pressure drop. Coil assembly pneumatically tested at 400 psig under water. Coil connections beveled for weld, flanged (optional) or grooved (optional).
I. Drift Eliminators: PVC, for long life and durability resistant to rot, decay and biological attack; formed, bonded together for strength and durability in block format for easy removal and replacement; self extinguishing with flame spread rating of 5 per ASTM E84-81a; 0.001% drift rate.
J. Water Level Control: Brass mechanical makeup water valve and plastic float with an adjustable linkage.
K. Water Recirculation Pump: Close-coupled, centrifugal type with mechanical seal. The pump motor shall be ____ horsepower totally enclosed for outdoor service on ____ volts, ____ hertz, and ____ phase.

2.4 MOTORS AND DRIVES
A. General requirements for motors are specified in Division 23 Section "Motors".
B. Enclosure Type: TEFC
C. Fan Motor Speed: Premium Efficient VFD Duty (Option: 2-speed)
D. Drive: Power Band Belt designed for 150% of the motor nameplate HP.
    1. Belt: V-belt type neoprene.
    2. Sheaves: Aluminum alloy, taper lock design.
    3. Bearings: Heavy duty, self-aligning bearings with extended grease lines and fittings.
    4. Fan Shaft: Solid steel shaft with forged bearing journals.
    5. Vibration Cutout Switch (Optional): Mechanical switch to de- energize fan motors if excessive vibration in NEMA 4 enclosure.

2.5 MAINTENANCE ACCESS
A. Access Door: A circular access door shall be located above the basin to allow for easy access to the pan interior.
B. Ladders (Optional): Aluminum, vertical complying with 29 CFR 1910.27.

2.6 SOUND ATTENUATION (OPTIONAL)
A. Inlet Attenuation: Materials to be same as fan section. Baffled panels shall change the path of air entry and capture radiated noise. External belt adjustment and lubrication points shall be provided.
B. Discharge Attenuation: Straight-sided discharge hood with insulated baffles to reduce the overall sound level of the discharge air. A large access panel to allow access to the water distribution system and drift eliminators shall be provided.