PART 1 - GENERAL
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, induced draft counterflow 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 cooling tower thermal performance according to CTI Standard 201.
    2.Test and certify cooling tower 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.

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

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

2.3 INDUCED-DRAFT, COUNTERFLOW CLOSED CIRCUIT COOLERS
A. Description: Factory assembled and tested, induced draft counterflow closed circuit cooler complete with coil, fill, fan, louvers, 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: Axial propeller, individually adjustable wide chord blade extruded aluminum installed in a closely fitted cowl with venturi air inlet for maximum efficiency, covered with a heavy gauge hot dipped Galvanized Steel fan guard.
    2. Maximum sound pressure level of _____dB(A) measured at 5 feet above the fan discharge during full speed operation in accordance with CTI Standard ATC-128.
D. Water Distribution System: Non-corrosive materials.
    1. Evenly distribute of water over fill material with pressurized spray tree.
       a. Pipes: Schedule 40 PVC, Non-corrosive Materials
       b. Nozzles: Non-clogging, ABS Plastic, 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: Galvanized Steel. Type 304 Stainless Steel Optional:
    1. Removable stainless-steel strainer with openings smaller than nozzle orifices.
    2. Joints: Bolted and sealed watertight or welded.
    3. Overflow, makeup and side drain connections
    4. Flume plate between cells (for multiple-cell units) or Equalizer connection (for multiple- closed circuit cooler system).
G. 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).
H. Casing: Galvanized Steel. Type 304 Stainless Steel Optional:
    1. Casing panels shall totally encase the fill media to protect the fill from damage due to direct atmospheric contact.
    2. Fasteners: Corrosion resistance equal to or better than materials being fastened.
    3. Joints: Sealed watertight.
    4. Welded Connections: Continuous and watertight
I. Fill Media: PVC; resistant to rot, decay and biological attack; formed, crossfluted bonded together for strength and durability in block format for easy removal and replacement; suitable for use as a working surface; self extinguishing with flame spread rating of 5 per ASTM E84-81a; able to withstand continuous operating temperature of 130°F; and fabricated, formed and installed by the manufacturer to ensure water breaks up into droplets.
J. Drift Eliminators: Same material as Fill. 0.001% drift rate.
K. Air Inlet Louvers: Formed PVC; designed "Sight Tight" to completely block direct sunlight from entering and water from splashing out of the closed circuit cooler.
L. Water Level Control: Brass mechanical makeup water valve and plastic float with an adjustable linkage.
M. 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 15 Section "Motors".
B. Enclosure Type: TEAO or TEFC
C. Motor Speed: Premium Efficient VFD Duty (Option: 2-speed)
D. Drive: Power Band Belt designed for 150% of the motor nameplate HP.
    1. Belt: Mutli-groove, solid back V-belt type neoprene reinforced with polyester cord.
    2. Sheaves: Aluminum alloy if located inside the airstream.
    3. Bearings: Heavy duty, self-aligning pillow block bearings with lubrication lines extended to side access door. Minimum L10 life for bearings shall be 75,000 hours. Provide extended grease lines and fittings.
    4. Vibration Cutout Switch: Mechanical switch to de- energize fan motors if excessive vibration in NEMA 4 enclosure.

2.5 MAINTENANCE ACCESS
A. Internal Working / Service Platforms: Provide a complete internal working platform and ladder system for service of all drive components. A suitable working platform may be constructed of the fill media for counterflow closed circuit coolers. If a crossflow cooler is used, provide an internal walkway with ladder and elevated working platform to allow for service and maintenance to motor and drive assembly.
B. Handrails/Grabrails: Galvanized steel pipe complying with 29 CFR 1910.23. If access to fan deck is required, supply a perimeter handrail with ladder from grade to fan deck.
C. Ladders: Aluminum, sloped "ships type" with grabrail or vertical complying with 29 CFR 1910.27.