Attachment 28 - 236514.13 fl - open-circuit, induced-draft, counterflow cooling towers.pdf

16.31.001 / FAA Hangars 8 and 9 Addm. #3 Dated 8/21/17

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DRAFT, COUNTERFLOW

COOLING TOWERS

SECTION 236514.13 - OPEN-CIRCUIT, INDUCED-DRAFT, COUNTERFLOW COOLING TOWERS

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary

Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. Section includes factory-assembled, open-circuit, induced-draft, counterflow cooling towers.

1.3 DEFINITIONS

A. SCCR: Short-circuit current rating.

1.4 ACTION SUBMITTALS

A. Product Data: For each type of product.

1. Include rated capacities, pressure drop, fan performance data, rating at selected points indicated, and furnished specialties and accessories.

2. Maximum flow rate.

3. Minimum flow rate.

4. Pressure required at cooling tower supply piping connections.

5. Pressure required at basin heater supply piping connections.

6. Pressure required at collection basin sweeper supply piping connections.

7. Drift loss as percent of design flow rate.

8. Volume of water in suspension for purposes of sizing remote storage.

9. Sound:

a. Sound pressure levels for operation with fan off, fan at minimum speed, and design speed. If sound requirements are indicated at a specific distance, submit performance using same distance for comparative analysis.

10. Fan airflow at design conditions, brake horsepower, and drive losses (indicated in horsepower and percent of brake horsepower).

11. Fan motor electrical characteristics including, but not limited to, speed, voltage, phase, hertz, amperage, efficiency, and power factor at 100, 75, 50, and 25 percent of nameplate horsepower.

12. Electrical power requirements for each cooling tower component requiring power.

B. Shop Drawings:

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1. Manufacturer's drawings of assembled cooling towers, control panels, sections, and elevations.

2. Assembled unit dimensions.

3. Diagram showing each separate piece requiring field assembly.

4. Shipped sub-assembly dimensions and weights for field assembly.

5. Assembled unit weight without water.

6. Operating weight and load distribution.

7. Unit vibration isolation.

8. Required clearances for maintenance and operation.

9. Sizes and dimensioned locations of piping and wiring connections.

10. Diagrams for power, signal, and control wiring.

1.5 INFORMATIONAL SUBMITTALS

A. Coordination Drawings:

1. Drawings on which the following items are shown and coordinated with each other, using input from installers of the items involved:

a. Structural supports.

b. Piping roughing-in requirements.

c. Conduit and wiring roughing-in requirements for controls and electrical power, including spaces reserved for controls and electrical equipment.

d. Access requirements, including working clearances for controls and electrical equipment, and service clearances. Mark and label clearances.

2. Drawings showing plans, sections, and elevation views, drawn to scale of at least 1/4 inch

= 1 foot.

3. Each view to show screened background with the following:

a. Structural grids.

b. Adjacent walls, floors, and roofs.

c. Equipment and products of other trades that are located in vicinity of cooling towers and are part of final installation, such as, controls, power, lighting, fire-suppression systems, and plumbing systems.

B. Product Certificates: For certification required in "Quality Assurance" Article.

C. Field Test Reports: Include startup service reports.

D. Source quality-control reports.

E. Field quality-control reports.

F. Sample Warranty: For special warranty.

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1.6 CLOSEOUT SUBMITTALS

A. Operation and Maintenance Data: For each cooling tower to include in emergency, operation, and maintenance manuals.

B. Instructional Videos: Including those that are prerecorded and those that are recorded during training.

1.7 MAINTENANCE MATERIAL SUBMITTALS

A. Belts:

1. Furnish one set(s) of matching belts for each unique belt configuration and size furnished.

B. Tool Kit:

1. A tool kit specially designed by cooling tower manufacturer for use in servicing cooling tower(s) furnished.

2. Special tools required to service components not readily available to Owner service personnel in performing routine maintenance.

3. Lockable case with hinged cover, marked with large and permanent text to indicate the special purpose of tool kit, such as "Cooling Tower Tool Kit." Text size shall be at least

1 inch high.

4. A list of each tool furnished. Permanently attach the list to underside of case cover. Text size shall be at least 1/2 inch high.

C. Touchup Coating: 32-oz. container of paint coating used. Label outside of container with detailed description of coating to allow for procurement of a matching coating in the future.

1.8 QUALITY ASSURANCE

1.9 DELIVERY, STORAGE, AND HANDLING

A. Coordinate requirements for multi-piece assembly for shipment. Limit the number of separate pieces for field installation to as few as possible.

B. If factory assembly of multiple pieces is required for testing or other reasons, disassemble cooling tower into major assemblies as required by installation before packaging for shipment.

1. Clearly label each separate package with a unique designation and include with assembly instructions for each complete cooling tower.

2. Install seals on gear-drive assemblies to eliminate oil leakage during shipment if shipped with oil.

1.10 WARRANTY

A. Special Warranty: Manufacturer agrees to repair or replace the following components of cooling towers that fail in materials or workmanship within specified warranty period:

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1. All components of cooling tower.

2. Fan assembly including fan, drive, and motor.

3. Warranty Period: Five years from date of Substantial Completion.

PART 2 - PRODUCTS

2.1 MANUFACTURERS

A. Manufacturers: Subject to compliance with requirements, provide products by one of the following:

1. Baltimore Aircoil Company.

2. EVAPCO, Inc.

3. Marley Cooling Technologies; SPX Cooling Technologies.

2.2 PERFORMANCE REQUIREMENTS

A. ASHRAE/IES 90.1 Compliance: Applicable requirements in ASHRAE/IES 90.1.

B. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location and application.

C. Operation Following Loss of Normal Power:

1. Equipment, associated factory- and field-installed controls, and associated electrical equipment and power supply connected to backup power system shall automatically return equipment and associated controls to the operating state occurring immediately before loss of normal power without need for manual intervention by an operator when power is restored either through a backup power source, or through normal power if restored before backup power is brought on-line.

2. Include means and methods required to satisfy requirement even if not explicitly indicated.

D. Vibration:

1. Rotating assemblies shall be dynamically balanced to achieve a balance level of "good" while complying with industry-standard requirements for cooling towers.

2. Critical speed shall be at least 115 percent of design speed.

2.3 DESIGN ARRANGEMENT

A. Counterflow design with airflow from all sides and induced-draft, top-mounted axial fan and pressurized pipe distribution.

2.4 CASING AND FRAME

A. Casing Material: Stainless steel.

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B. Frame Material: stainless steel.

C. Hardware: stainless steel.

D. Joints and Seams: Sealed watertight.

E. Welded Connections: Sealed watertight.

2.5 COLLECTION BASIN

A. Factory-Assembled Collection Basin:

1. Material: Stainless Steel

2. Hardware: stainless steel.

3. Joints and Seams: Sealed watertight.

4. Welded Connections: Sealed watertight.

5. Removable stainless-steel strainer with openings smaller than nozzle orifices.

6. Overflow and drain connections.

7. Makeup-water connection.

8. Outlet Connection: Configured to mate to ASME B16.5, Class 150 flange.

9. Removable equalization flume plate between adjacent cells of multiple-cell towers.

10. Equalizer connection for field-installed equalizer piping configured to mate to

ASME B16.5, Class 150 flange.

11. Basin Sweeper Distribution Piping and Nozzles:

a. Pipe Material: PVC or CPVC, Schedule 40 or heavier, treated with UV inhibitors and intended for continuous exposure to direct sunlight with degradation.

b. Nozzle Material: Plastic.

c. Configure piping and nozzles to minimize sediment from collecting in the collection basin.

d. Basin penetrations sealed watertight.

e. Field Connections: Threaded or flanged depending on pipe size. Thread for sizes through 2 1/2 and flanged for larger sizes.

2.6 COLLECTION BASIN MAKEUP-WATER ASSEMBLY

A. Mechanically Operated, Collection Basin Water-Level Control: Manufacturer's standard adjustable, mechanical float assembly and valve.

B. Electric/Electronic, Collection Basin Water-Level Controller with Makeup-Water Valve:

1. Enclosures: NEMA 250, Type 4.

2. Sensor: Solid-state controls with multiple electrode probes and relays factory wired to a terminal strip to control makeup-water valve and low- and high-level alarms.

3. Electrode Probes: Stainless steel.

4. Water Stilling Chamber: Stainless Steel.

5. Makeup-Water Valve:

a. Slow closing with stainless-steel body.

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b. Valve actuator controlled and powered through level controller in response to water-level set point.

c. Actuator Enclosure: NEMA 250, Type 4.

d. Fail Position: Closed.

e. Action: [Two position] [or] [modulating].

6. Electrical Connection Requirements: 120-V ac, single phase, 60 Hz.

2.7 COLLECTION BASIN HEATER

A. Electric Heater:

1. Stainless-Steel Electric Immersion Heaters: Installed in a threaded coupling on the side of the collection basin.

2. Heater Control Panel: Mounted on the side of each cooling tower cell.

3. Enclosure: NEMA 250, Type 4.

4. Magnetic contactors controlled by a temperature sensor/controller to maintain collection basin water-temperature set point. Water-level probe shall monitor cooling tower water level and de-energize the heater when the water reaches low-level set point.

5. Control-circuit transformer with primary and secondary side fuses.

6. Terminal blocks with numbered and color-coded wiring to match wiring diagram.

7. Single-point, field-power connection to a circuit breaker and heater branch circuiting complying with NFPA 70.

8. Factory Wiring Method: Metal raceway for factory-installed wiring outside of enclosures, except connections to each electric basin heater shall be liquid tight conduit.

a. Raceway shall be corrosion-resistant stainless steel or PVC coated steel.

B. Hot-Water-Coil Heater: Manufacturer's standard heater with indicated capacity.

C. Steam-Coil Heater: Manufacturer's standard heater with indicated capacity.

D. Steam-Injector Heater: Manufacturer's standard heater with indicated capacity.

2.8 PRESSURIZED DISTRIBUTION NETWORK

A. Main header and lateral branch piping designed for even distribution over fill throughout the entire flow range without the need for balancing valves and for connecting individual, easily removable, non-clogging spray nozzles.

B. Pipe Material: Fiberglass or Schedule 40 PVC.

C. Spray Nozzle Material: Plastic polypropylene or PVC.

D. Piping Supports: Corrosion-resistant hangers and supports to resist movement during operation and shipment.

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2.9 FILL

A. Materials: PVC, with maximum flame-spread index of 5 according to ASTM E 84.

B. Fabrication: Fill-type sheets, fabricated, formed, and bonded together after forming into removable assemblies that are factory installed by manufacturer.

C. Fill Material Operating Temperature: Suitable for entering-water temperatures up through 120 deg F.

D. Hardware: stainless steel.

2.10 DRIFT ELIMINATORS

A. Material: PVC; with maximum flame-spread index of5 according to ASTM E 84.

B. UV Treatment: Inhibitors to protect against damage caused by UV radiation.

C. Configuration: Multipass, designed and tested to reduce water carryover to 0.005 percent of design flow rate indicated.

D. Hardware: stainless steel.

2.11 AIR INLET

A. Air-Intake Louvers:

1. Material: PVC.

2. UV Treatment: Inhibitors to protect against damage caused by UV radiation.

3. Multiple, easily removable sections arranged to uniformly direct air into cooling tower, to minimize air resistance, to block direct sunlight, and to prevent water from splashing out of tower during all modes of operation including operation with fans off.

2.12 FAN AND DRIVE ASSEMBLY

A. Axial Fan: Balanced at the factory.

1. Blade Material: Aluminum.

2. Blade Pitch: Field adjustable.

3. Fan Shaft: Stainless steel.

4. Fan Shaft Bearings: Self-aligning ball or roller bearings with moisture-proof seals and premium, moisture-resistant grease suitable for temperatures between minus 20 and plus

300 deg F. Bearings designed for an L-10 life of 40,000 hours.

5. Bearings Grease Fittings: Extended lubrication lines to an easily accessible location.

B. Belt Drive:

1. Service Factor: 1.5 based on motor nameplate horsepower.

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2. Sheaves: Fan and motor shafts shall have taper-lock sheaves fabricated from corrosion-resistant materials.

3. Belt: One-piece, multi-grooved, solid-back belt.

4. Belt Material: Oil resistant, non-static conducting, and constructed of neoprene polyester cord.

5. Belt-Drive Guard: Comply with OSHA regulations.

C. Gear Drive: Right angle, reduced speed, and designed for cooling tower applications according to CTI STD 111. Motor and gear drive shall be aligned before shipment.

1. Gear Drive and Coupling Service Factor: 2.0 based on motor nameplate horsepower.

2. Housing: Cast iron, with epoxy or polyurethane finish, beveled high-strength steel gears continuously bathed in oil, and with lubrication to other internal parts at all operating speeds.

3. Mounting: Directly mounted to fan hub and connected to motor so motor shaft is in horizontal position.

4. Operation: Able to operate both forward and in reverse. Able to operate throughout entire speed range from design speed indicated down to 10 of design speed.

5. Drive-to-Motor Connection: Close coupled to motor using a flexible coupling.

6. Drive-to-Motor Connection: Connected to motor located outside of cooling tower casing by a full-floating drive shaft.

7. Drive Shaft Material: Stainless steel, and fitted with flexible couplings on both ends.

8. Drive Guards: Exposed shaft and couplings shall have guards according to OSHA regulations.

9. Extend oil fill, drain, and vent to outside of cooling tower casing using stainless-steel piping. Include oil-level sight glass.

D. Fan Motor:

1. Comply with NEMA MG 1 unless otherwise indicated.

2. Description: NEMA MG 1, Design B, as required to comply with capacity and torque characteristics; medium induction motor.

3. Capacity and Torque Characteristics: Sufficient to start, accelerate, and operate connected loads at designated speeds, at installed altitude and environment, with indicated operating sequence, and without exceeding nameplate ratings or considering service factor.

4. Motor Enclosure: Totally enclosed fan-cooled (TEFC).

5. Rotor: Random-wound, squirrel cage.

6. Energy Efficiency: NEMA Premium Efficient.

7. Service Factor: 1.15.

8. Temperature Rise: Match insulation rating.

9. Insulation: Class F.

10. Variable-Speed Motors: Inverter-duty rated per NEMA MG 1, Section IV, "Performance

Standard Applying to All Machines," Part 31, "Definite-Purpose, Inverter-Fed, Polyphase

Motors."

11. Motor Location: Mounted outside of cooling tower casing and cooling tower discharge airstream.

12. Motor Base: Adjustable, or other suitable belt-tensioning provisions.

E. Hardware: stainless steel.

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2.13 AIR DISCHARGE

A. Low-Profile Fan Discharge Stack:

1. Manufacturer's standard low-profile design.

2. Material: Material to match casing.

3. Stack Termination: Wire-mesh, stainless-steel screens; segmented into multiple removable pie sections and complying with OSHA regulations.

B. Hardware: stainless steel.

2.14 ELECTRICAL POWER

A. Factory Install: A disconnect switch for each fan motor.

1. Locate in a convenient and field-accessible location within sight of motor.

2. Installation shall comply with NFPA 70.

3. Wire, Conduit, and Enclosures:

a. Minimum Conduit Size: 0.75 inch.

b. Materials: Corrosion resistant and constructed of 300L series stainless steel or

PVC coated steel.

c. Motor Termination: Liquidtight conduit, not to exceed 36 inches long.

d. Supports: Support conduits, boxes, and enclosures using corrosion-resistant fastening hardware constructed of stainless steel.

1)

e. Boxes, Condulets, and Enclosures: NEMA 250, Type 4.

B. Disconnect Switches:

1. Specification Grade; "Heavy Duty Type"; "quick-make," "quick-break" construction.

2. Three pole, fused.

3. 600-V rated.

4. Minimum SCCR: As required by electrical power distribution system, but not less than

65,000 A.

5. Enclosure: NEMA 250, Type 4.

6. Operating handle shall be of box-mounted type that directly drives switch mechanism.

7. Disconnect switch shall use a flange-operated visible blade that is close coupled to a vertical-lift-type handle that achieves a positive visible indication of disconnect with cover open or closed.

8. Disconnect switch shall have a defeatable, front-accessible, mechanical interlock to prevent opening of cover when switch is in "ON" position, and to prevent turning switch

"ON" when the door is open.

9. Include a solid neutral as required by authorities having jurisdiction.

10. Disconnect switch shall have a ground lug for ground wire termination.

11. Operating handle shall be lockable in open position.

12. Horsepower rated.

13. Feed through or double lugged.

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C. Variable-Frequency Controllers:

1. Description: NEMA ICS 2; arranged to achieve motor variable speed by adjusting output voltage and frequency.

2. Enclosure: Unit mounted, NEMA 250, Type 4, with hinged full-front access door with lock and key.

3. Externally Operated Disconnect: with lockable handle.

4. Minimum SCCR: As required by electrical power distribution system, but not less than

65,000 A.

5. Technology: Pulse-width-modulated (PWM) output with insulated gate bipolar transistors

(IGBT); suitable for variable torque loads.

6. Controller shall consist of a rectifier converter section, a digital/analog driver regulator section, and an inverter output section.

7. Output Rating: Three phase; with voltage proportional to frequency throughout voltage range.

8. Output signal shall be programmed to not cause mechanical vibration issues with fan drive assembly.

9. Operating Requirements:

a. Input AC Voltage Tolerance: 10 percent.

b. Input frequency tolerance of 60 Hz, plus or minus 2 Hz.

c. Capable of driving full motor load, without derating.

d. Minimum Efficiency: 96 percent at 60 Hz, full load.

e. Minimum Displacement Primary-Side Power Factor: 95 percent.

f. Overload Capability: 1.05 times the full-load current for 7 seconds.

g. Starting Torque: As required by fan and motor drive assembly.

h. Speed Regulation: 1 percent.

i. Speed Range: 10:1 speed range.

j. To avoid equipment resonant vibrations, include critical speed lockout circuitry to allow bands of operating frequency at which controller shall not operate continuously.

k. Capable of being restarted into a motor coasting in either the forward or reverse direction without tripping.

10. Controller Adjustability Capabilities: Minimum and maximum output frequency, acceleration and deceleration, and current limit.

11. Self-Protection and Reliability Features: Subjecting the controller to any of the following conditions shall not result in component failure or the need for replacement:

a. Overtemperature.

b. Short circuit at controller output.

c. Ground fault at controller output. Variable-frequency controller shall be able to start a grounded motor.

d. Open circuit at controller output.

e. Input undervoltage.

f. Input overvoltage.

g. Loss of input phase.

h. Reverse phase.

i. AC line switching transients.

j. Instantaneous overload, line to line or line to ground.

k. Sustained overload exceeding 100 percent of controller rated current.

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l. Starting a rotating motor.

m.

12. Motor Protection: Controller shall protect motor against overvoltage and undervoltage, phase loss, reverse phase, overcurrent, overtemperature, and ground fault.

13. Automatic Reset and Restart:

a. Capable of multiple restarts after controller fault or on return of power after an interruption and before shutting down for manual reset or fault correction.

b. Capable of automatic restart on phase-loss and overvoltage and undervoltage trips.

14. Visual Indication: On face of controller; indicating the following conditions:

a. Power on.

b. Run.

c. Various faults with alarm status.

15. Operator Interface: Start-stop and auto-manual selector with manual-speed-control potentiometer.

2.15 CONTROLS

A. Vibration Switch: For each fan drive.

1. Enclosure: NEMA 250, Type 4.

2. Vibration Detection: Sensor with a field-adjustable, acceleration-sensitivity set point in a range of 0 to 1 g and frequency range of 0 to 3000 cycles per minute. Cooling tower manufacturer shall recommend switch set point for proper operation and protection.

3. Switch shall have field connection to a control system hardwired connection to fan motor electrical circuit.

4. Switch shall, on sensing excessive vibration, signal an alarm for connection to control system and shut down the fan.

B. Vibration Transmitter with Switch: For each fan drive.

1. Enclosure: NEMA 250, Type 4X.

2. Display: Local display of measured value, power, and alarm.

3. Vibration Detection: Sensor with a field-adjustable, acceleration-sensitivity set point.

a. Cooling tower manufacturer shall select range that is suitable for cooling tower and recommend switch set point for proper operation and protection.

4. Transmitter: Continuous vibration level indication through a 4- to 20-mA signal for connection to control system.

5. Switch:

a. Relay and switch with manual-reset button for field connection to control system and hardwired connection to fan motor electrical circuit.

b. Switch shall, on sensing excessive vibration, signal an alarm to control system and shut down the fan.

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6. Mounting: Locate out of cooling tower discharge airstream and mount in a location that is accessible and where display is easily viewable.

7. Field Electrical Connection Requirements: 120 V, single phase, 60 Hz.

C. Control Package:

1. Factory installed and wired, and functionally tested at factory before shipment.

2. NEMA 250, Type 4 enclosure with removable internally mount backplate.

3. Control-circuit transformer with primary and secondary side fuses.

4. Terminal blocks with numbered and color-coded wiring to match wiring diagram. Spare wiring terminal block for connection to external controls or equipment.

5. Microprocessor-based controller for automatic control of fan based on cooling tower leaving-water temperature with control features to improve operating efficiency based on outdoor ambient wet-bulb temperature by using adaptive logic.

6. Fan motor sequencer for multiple-cell and two-speed applications with automatic lead stage rotation.

7. Collection basin level controller complying with requirements in "Electric/Electronic, Collection Basin Water-Level Controller with Makeup-Water Valve" Paragraph in

"Collection Basin Makeup-Water Assembly" Article.

8. Electric basin heaters with temperature control and low-water-level safety switch for each cell, complying with requirements in "Collection Basin Heater" Article.

9. Vibration switch for each fan, complying with requirements in "Vibration Switch"

Paragraph.

10. Single-point, field-power connection to a fused disconnect switch for each cooling tower cell.

a. Branch power circuit to each motor and electric basin heater and to controls with a disconnect switch or circuit breaker.

b. NEMA-rated motor controller, hand-off-auto switch, and overcurrent protection for each motor. Include variable-frequency controller with manual bypass and line reactors for each variable-speed motor indicated.

11. Factory-installed wiring outside of enclosures shall be in metal raceway, except make connections to each motor and electric basin heater with liquidtight conduit.

12. Visual indication of status and alarm for each motor.

13. Audible alarm and silence switch.

14.

15. Cooling tower shall have hardware to enable control system to remotely monitor and display the following:

a. Operational status of each motor.

b. Cooling tower leaving-fluid temperature.

c. Fan vibration alarm.

d. Oil-level alarm.

e. Collection basin high- and low-water-level alarms.

2.16 SERVICE ACCESS

A. Doors:

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1. Large enough for personnel to access cooling tower internal components.

2. Doors shall be hinged with handles operable from both sides of the door.

3. Door materials shall match casing.

4. Hinges and handles shall be stainless steel.

B. External Ladders with Safety Cages: stainless-steel fixed ladders with ladder extensions to access external platforms and top of cooling tower from adjacent grade without the need for portable ladders. Comply with 29 CFR 1910.27.

C. External Platforms with Handrails: stainless-steel bar grating at cooling tower access doors when cooling towers are elevated and not accessible from grade.

D. External Motor Platforms with Handrails: stainless-steel bar grating.

E. Fan Deck Floor between Cooling Tower Cells:

1. Factory furnish reinforced fan deck floor panels between cooling tower cells for field installation.

2. Floor materials shall match adjacent cooling tower cell fan deck.

3. Fan deck floor shall fasten to and be supported by framing that is attached to cooling tower cells.

4. Frame shall be constructed of same materials as cooling tower frame.

F. Handrail: stainless steel complete with kneerail and toeboard, around external platforms and top of cooling tower. Comply with 29 CFR 1910.23.

G. Internal Platforms: stainless-steel bar grating.

1. Spanning the collection basin from one end of cooling tower to the other and positioned to form a path between. Platform shall be elevated so that all parts are above the high water level of the collection basin.

2. Elevated internal platforms with handrails accessible from fixed vertical ladders to access the fan drive assembly when out of reach.

H. Hardware: Galvanized steel when connecting galvanized-steel components; stainless steel when connecting other materials.

2.17 HOISTING ASSEMBLY

A. Hoisting assembly consisting of pedestal base, davit arm, and winch to accommodate lowering and raising cooling tower components from their installed location to the base of cooling tower supports.

1. Cooling tower components serviceable by hoisting assembly shall include, but not be limited to, fan stack, fan, fan drive, and fan motor.

2. Hoisting assembly shall be designed to accommodate heaviest single component plus a safety factor of 1.5.

3. Construct cooling tower structural supports and reinforcing to accommodate lifting heaviest load with safety factor.

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B. Pedestal Base:

1. Equip each cooling tower cell with a pedestal base to accommodate an easily removable davit arm and winch assembly.

2. Position pedestal base at a location on cooling tower for hoisting assembly coverage to fan, fan motor, and fan drive assembly.

3. Pedestal base design shall be open-socket, or comparable, design that is configured to accept and secure an inserted portable davit arm.

4. Fit each pedestal base with an easily removable cap or plug designed to seal the open top of the base when the davit arm is not installed.

5. Fasten pedestal base to cooling tower using threaded hardware.

6. Construct pedestal base of 300L series stainless steel.

C. Davit Arm:

1. Each cooling tower cell shall have a davit arm.

2. Davit arm shall be an adjustable telescoping design with angular adjustment to accommodate varying lifting conditions required by the application.

3. Davit arm assembly shall be portable and capable of being relocated to any cooling tower cell pedestal base.

4. Construct davit arm of 300L series stainless steel.

D. Winch:

1. Each davit arm shall have a hand-operated winch.

a. Hand-operated winch with gear mechanism to limit force on handle to not more than 80 lb when lifting the heaviest component.

2. Coat winch body and exposed components with corrosion-resistant finish that is rated for outdoor duty in a highly corrosive environment and exposed to direct sunlight.

3. Winch cable shall be stainless steel and terminated with a stainless-steel hook and quick disconnecting mechanism. Cable length shall be at least 1.5 times actual length required for application.

E. Hardware: 304 or 316 series stainless steel.

F. Nameplate:

1. Stamped or engraved aluminum or stainless-steel nameplate with rated load capacity on each davit arm and pedestal.

2. Letter size legible from a distance 60 inches and not less than 1/2 inch.

3. Fasten nameplate at multiple points with stainless-steel rivets or screws.

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2.18 SOURCE QUALITY CONTROL

PART 3 - EXECUTION

3.1 EXAMINATION

A. Examine cooling towers before installation. Reject cooling towers that are damaged.

B. Before cooling tower installation, examine roughing-in for tower support, anchor-bolt sizes and locations, piping, controls, and electrical connections to verify actual locations, sizes, and other conditions affecting cooling tower performance, maintenance, and operation.

1. Cooling tower locations indicated on Drawings are approximate. Determine exact locations before roughing-in for piping, controls, and electrical connections.

2. Verify sizes, locations, and anchoring attachments of structural-steel support structures.

3. Verify sizes and locations of roof curbs, equipment supports, and roof penetrations with actual equipment.

C. Proceed with installation only after unsatisfactory conditions have been corrected.

3.2 INSTALLATION

A. Install cooling towers on support structure.

B. Install anchor bolts to elevations required for proper attachment to supported equipment.

C. Maintain manufacturer's recommended clearances for service and maintenance.

D. Maintain clearances required by governing code.

E. Loose Components: Install components, devices, and accessories furnished by manufacturer, with cooling tower, that are not factory mounted.

1. Loose components shall be installed by Contractor under supervision of manufacturer's factory-trained service personnel.

3.3 PIPING CONNECTIONS

A. Piping installation requirements are specified in other Sections. Drawings indicate general arrangement of piping, fittings, and specialties.

B. Where installing piping adjacent to cooling towers, allow space for service and maintenance.

C. Install flexible pipe connectors at pipe connections of cooling towers mounted on vibration isolators.

D. Install drain piping with valve at cooling tower drain connections and at low points in piping.

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E. Connect cooling tower overflows and drains, and piping drains, to sanitary sewage system.

F. Makeup-Water Piping:

1. Comply with applicable requirements in Section 221116 "Domestic Water Piping."

2. Connect to makeup-water connections with shutoff valve, plugged tee with pressure gage, flow meter, and drain connection with valve and union.

G. Supply and Return Piping:

1. Comply with applicable requirements in Section 232113 "Hydronic Piping" and

Section 232116 "Hydronic Piping Specialties."

2. Connect to entering cooling tower connections with shutoff valve, strainer, balancing valve, thermometer, plugged tee with pressure gage, flow meter, and drain connection with valve.

3. Connect to leaving cooling tower connection with shutoff valve thermometer, plugged tee with full port ball valve for portable field instruments, and drain connection with valve.

4. Make connections to cooling tower with a flange.

H. Equalizer Piping:

1. Piping requirements to match supply and return piping.

2. Connect an equalizer pipe, full size of cooling tower connection, between tower cells.

3. Connect to cooling tower with shutoff valve and drain connection with valve.

4. Make connections to cooling tower with a flange.

I. Basin Sweeper Piping:

1. Comply with applicable requirements in Section 232113 "Hydronic Piping" and

Section 232116 "Hydronic Piping Specialties."

2. Connect to supply connections with shutoff valve, flow meter, and drain connection with valve.

3. Connect to return connections with shutoff valve, balancing valve, flow meter, and drain connection with valve.

4. Make connections with a flange or union.

3.4 ELECTRICAL POWER CONNECTIONS

A. Connect field electrical power source to each separate electrical device requiring field electrical power. Coordinate termination point and connection type with Installer.

B. Comply with requirements in Section 260519 "Low-Voltage Electrical Power Conductors and

Cables" for wiring connections.

C. Ground equipment according to Section 260526 "Grounding and Bonding for Electrical

Systems" for grounding connections.

D. Install nameplate for each electrical connection indicating electrical equipment designation and circuit number feeding connection. Nameplate shall be laminated phenolic layers of black with engraved white letters at least 1/2 inch high. Locate nameplate where easily visible.

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3.5 CONTROLS CONNECTIONS

A. Install control and electrical power wiring to field-mounted control devices.

B. Connect control wiring between cooling towers and other equipment to interlock operation as required to achieve a complete and functioning system.

C. Connect control wiring between cooling tower control interface and control system for HVAC for remote monitoring and control of cooling towers. Comply with requirements in

Section 230923 "Direct Digital Control (DDC) System for HVAC."

D. Install label at each termination indicating control equipment designation serving cooling tower and the I/O point designation for each control connection. Comply with requirements in

Section 260553 "Identification for Electrical Systems" for labeling and identifying products and installations.

3.6 FIELD QUALITY CONTROL

A. Perform tests and inspections with the assistance of a factory-authorized service representative.

B. Tests and Inspections: Comply with ASME PTC 23.

C. Cooling towers will be considered defective if they do not pass tests and inspections.

D. Prepare test and inspection reports.

3.7 STARTUP SERVICE

A. Perform startup service.

B. Inspect field-assembled components, equipment installation, and piping; controls; and electrical connections for proper assemblies, installations, and connections.

C. Obtain performance data from manufacturer.

1. Complete installation and startup checks according to manufacturer's written instructions and perform the following:

a. Clean entire unit including basins.

b. Verify that accessories are properly installed.

c. Verify clearances for airflow and for cooling tower servicing.

d. Check for vibration isolation and structural support.

e. Lubricate bearings.

f. Verify fan rotation for correct direction and for vibration or binding and correct problems.

g. Adjust belts to proper alignment and tension.

h. Operate variable-speed fans through entire operating range and check for harmonic vibration imbalance. Set motor controller to skip speeds resulting in abnormal vibration.

i. Check vibration switch setting. Verify operation.

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j. Verify water level in tower basin. Fill to proper startup level. Check makeup-water-level control and valve.

k. Verify operation of basin heater and control.

l. Verify that cooling tower air discharge is not recirculating air into tower or HVAC air intakes. Recommend corrective action.

m. Replace defective and malfunctioning units.

D. Start cooling tower and associated water pumps. Follow manufacturer's written starting procedures.

E. Prepare a written startup report that records the results of tests and inspections.

3.8 ADJUSTING

A. Set and balance water flow to each tower inlet.

B. Adjust water-level control for proper operating level.

C. Adjust basin heater control for proper operating set point.

3.9 DEMONSTRATION

A. Train Owner's maintenance personnel to adjust, operate, and maintain cooling towers.

1. Video record the training sessions.

2. Instructor shall be factory trained and certified.

3. Perform not less than 8 hours of training.

4. Train personnel in operation and maintenance and to obtain maximum efficiency in plant operation.

5. Perform instructional videos showing general operation and maintenance that are coordinated with operation and maintenance manuals.

6. Obtain Owner sign-off that training is complete.

7. Owner training shall be held at Project site.

END OF SECTION 236514.13