SECTION 15682

AIR COOLED WATER CHILLERS

PART 1 GENERAL

SECTION INCLUDES

Chiller package.

Charge of refrigerant and oil.

Controls and control connections.

Chilled water connections.

Starters.

Electrical power connections.

RELATED SECTIONS

Section 15170 - Motors

Section 15252 - Vibration Isolation.

Section 15510 - Hydronic Piping.

Section 15535 - Refrigeration Piping and Specialties.

Section 15540 - HVAC Pumps.

Section 15952 - Controls and Instrumentation.

Section 15990 - Testing, Adjusting, and Balancing.

Section 16180 - Equipment Wiring Systems.

REFERENCES

ANSI/ARI 590 - Reciprocating Water - Chilling Packages.

ANSI/ASHRAE 15 - Safety Code for Mechanical Refrigeration.

ANSI/ASHRAE 90A - Energy Conservation in New Building Design.

ANSI/ASME SEC 8 - Boiler and Pressure Vessel Code

ANSI/NEMA MG 1 - Motors and Generators.

ANSI/UL 465 - Central Cooling Air Conditioners.

SUBMITTALS

Submit shop drawings under provisions of Section [01300.] [01340.]

Submit shop drawings indicating components, assembly, dimensions, weights and loadings, required clearances, and location and size of field connections. Indicate valves, strainers, and thermostatic valves required for complete system.

Submit product data under provisions of Section [01300.] [01340.]

Submit product data indicating rated capacities, weights, specialties and accessories, electrical requirements and wiring diagrams.

Submit written certification that components of package not furnished by manufacturer have been selected in accordance with manufacturers requirements.

Submit manufacturer's installation instructions under provisions of Section [01300.] [01340.]

OPERATION AND MAINTENANCE DATA

Submit operations data under provisions of Section [01700.] [01730.]

Include start-up instructions, maintenance data, parts lists, controls, and accessories. Include trouble-shooting guide.

Submit maintenance data under provisions of Section [01700.] [01730.]

REGULATORY REQUIREMENTS

Conform to ANSI/ARI 590 code for testing and rating of reciprocating water chillers.

Conform to ANSI/UL 465 code for construction of reciprocating water chillers[.] [and provide UL label.]

Conform to ANSI/ASME SEC 8 Boiler and Pressure Vessel Code for construction and testing of reciprocating water chillers.

Conform to ANSI/ASHRAE 15 code for construction and operation of reciprocating water chillers.

Provide certification of inspection for conforming [authority having jurisdiction] [_______________] approval.

DELIVERY, STORAGE, AND HANDLING

Deliver products to site under provisions of Section [01600.] [01610.]

Store and protect products under provisions of Section [01600.] [01620.]

Comply with manufacturer's installation instructions for rigging, unloading, and transporting units.

Protect units on site from physical damage.

WARRANTY

Provide [five] [_____] year warranty under provisions of Section [01700.] [01740.]

Warranty: Include coverage for [compressor] [evaporator] [condenser] [complete assembly] including [materials.] [and] [labor.] [only.]

MAINTENANCE SERVICE

Furnish service and maintenance of complete assembly for [one year] [_____] from Date of Substantial Completion.

PART 2 PRODUCTS

MANUFACTURERS

[______________________________] Product [__________.]

[______________________________] Product [__________.]

[______________________________] Product [__________.]

Substitutions: Under provisions of Section [01600.] [01630.]

MANUFACTURED UNITS

Provide factory assembled and tested outdoor air cooled liquid chillers consisting of reciprocating compressors, condenser, evaporator, thermal expansion valve, refrigeration accessories, and control panel. Construction and ratings shall be in accordance with ANSI/ARI 590.

Provide [_____] air cooled water chillers, [each] having minimum capacity of [___] tons ([___] W) of refrigeration when delivering [_____] gpm ([_____] L/sec) of chilled water at [_____] degrees F ([_____] degrees C). No less than 0.0005 fouling factor, with air entering condenser at [_____] degrees F ([_____] degrees C) and power input of [_____] kW. Water head loss thru evaporator [_____] feet ([_____] Pa) maximum.

Provide minimum heat recovery capacity of [_____] Btu/hr ([_____] W), delivering [_____] gpm ([_____] L/Sec) of heated water at [_____] degrees F ([_____] degrees C) when supplied with [R-12] [R-22] refrigerant at [_____] degrees F ([_____] degrees C) saturated suction temperature. Fouling factor no less than 0.0005. Water head loss thru condenser [_____] feet ([_____] Pa) maximum.

COMPRESSORS

Construct semi-hermetic [or hermetic] reciprocating compressors with heat treated forged steel or ductile iron shafts, aluminum alloy connecting rods, automotive type pistons, rings to prevent gas leakage, suction and discharge valves, and sealing surface immersed in oil.

Statically and dynamically balance rotating parts and mount on [spring] [rubber-in-shear] vibration isolators. [Refer to Section 15252.]

Provide reversible, positive displacement, oil pump lubrication system with oil charging valve, oil level sight glass, oil filter, and magnetic plug on strainer, arranged to ensure adequate lubrication during starting, stopping, and normal operation.

Provide compressor with automatic capacity reduction equipment consisting of suction valve unloaders. Use lifting mechanism operated by [oil pressure.] [gas discharge pressure.] [solenoid valve.] Provide for unloaded compressor start.

Provide constant speed [1800] [3600] rpm compressor motor, suction gas cooled with solid state sensor and electronic winding overheating protection, designed for across-the-line starting. Refer to Section 15170. Furnish with starter.

Provide crankcase heater to evaporate refrigerant returning to crankcase during shut down. Energize heater [continuously.] [when compressor is not operating.]

EVAPORATOR

Provide shell and tube type evaporator, seamless or welded steel construction with cast iron or fabricated steel heads, seamless copper tubes or red brass tubes with integral fins, rolled or silver brazed into tube sheets. [Provide multiple refrigerant circuits on multiple compressor units.]

Design, test, and stamp refrigerant side for 225 psig (1550 kPa) working pressure and water side for 150 psig (1034 kPa) working pressure, in accordance with ANSI/ASME SEC 8.

Insulate with [0.75 inch (20 mm)] [1.5 inch (40 mm)] minimum thick flexible [expanded polyvinyl chloride] polyurethane foam] insulation with maximum K value of [0.28] [0.26] [0.15]. Provide heat tape to protect evaporator to [-20 degrees F (-29 degrees C).] [[_____] degrees F ([_____] -29 degrees C).]

Provide water drain connection and thermometer wells for temperature controller and low temperature cutout.

CONDENSERS

Construct condenser coils of aluminum fins mechanically bonded to seamless copper tubing. Provide sub-cooling circuits with liquid accumulators. Air test under water to 425 psig (2900kPa).

Provide vertical discharge [direct] [belt] driven propeller type condenser fans with fan guard on discharge. [Equip with roller or ball bearings with grease fittings extended to outside of casing.] Provide factory mounted, louvered, galvanized steel coil guard panels[.] [with lint screens.]

Provide fan motors with permanently lubricated ball bearings and built-in current and overload protection. Refer to Section 15170.

ENCLOSURES

House components in [welded steel frame with] galvanized steel panels with weather resistant, baked enamel finish.

Mount starters and disconnects in weatherproof panel provided with full opening access doors. Provide mechanical interlock to disconnect power when door is opened.

HEAT RECOVERY CONDENSERS

Provide condensers of shell and tube type, seamless or welded steel construction with cast iron or fabricated steel heads, seamless copper tubes or red brass tubes with integral fins, rolled or silver brazed into tube sheets.

Design, test, and stamp refrigerant side for 450 psig (3100 kPa) working pressure in accordance with ANSI/ASME SEC. 8

Provide 450 psig (3100 kPa) safety relief valve on condenser shell.

Design, test and stamp water side for 150 psig (1034 kPa) working pressure in accordance with ANSI/ASME SEC. 8.

REFRIGERANT CIRCUIT

Provide refrigerant circuits, factory supplied and piped. Refer to Section 15535.

Provide for each refrigerant circuit:

Liquid line solenoid valve.

Filter dryer (replaceable core type).

Liquid line sight glass and moisture indicator.

Thermal expansion valve sized for maximum operating pressure.

Charging valve.

Insulated suction line.

Discharge line check valve.

Compressor discharge service valve.

Condenser pressure relief valve.

CONTROLS

On chiller, mount weatherproof steel control panel, containing starters power and control wiring, [molded case disconnect switch,] factory wired with single point power connection.

For each compressor, provide [across-the-line] [part winding] starter, non-recycling compressor overload, starter relay, and control power transformer or terminal for controls power. Provide manual reset current overload protection.

Provide the following safety controls [with indicating lights] arranged so that operating any one will shut down machine and require manual reset:

Low chilled water temperature switch.

High discharge pressure switch[.] [for each compressor.]

Low suction pressure switch[.] [for each compressor.]

Oil pressure switch.

Flow switch in chilled water line.

Relay for remote mounted emergency shut-down switch.

Provide the following operating controls:

Multi-step chilled water temperature controller which cycles compressors[.] [and activates cylinder unloaders.]

Five minute off timer prevents compressor from short cycling.

Periodic pump-out timer to pump down on chilled water flow and high evaporator refrigerant pressure.

Solenoid valve between heat recovery condenser and receiver to limit refrigerant level in condenser.

Load limit thermostat to limit compressor loading on high return water temperature.

Low ambient control consisting of external damper assembly, controls head pressure for operation down to 0 degrees F (-18 degrees C).

Hot gas bypass sized for minimum compressor loading [on one compressor only], bypasses hot refrigerant gas to evaporator.

Provide pre-piped gage board with pressure gages for suction and discharge refrigerant pressures, and oil

pressures[.] [for each compressor.]

For multiple units, provide remote mounted sequence panel to allow operation in [series] [parallel] with lead-lag switching.

PART 3 EXECUTION

INSTALLATION

Install in accordance with manufacturer's instructions.

Align chiller package on steel or concrete foundations.

Install units in vibration isolation. Refer to Section 15252.

Connect to electrical service.	Refer to Section 16180.

Connect to chilled water piping.	Refer to Section 15510. On inlet, provide thermometer well for temperature controller, [thermometer well for temperature limit controller,] [flow switch,] [flexible pipe connecter,] and shut-off valve. On outlet, provide [flexible pipe connecter] and [shut-off] [balancing] valve.

Connect to heat recovery condenser water piping.	Refer to Section 15510. On inlet, provide [flexible pipe connecter and] shut-off valve. On outlet, provide [flexible pipe connecter and] [shut-off] [balancing] valve.

Arrange piping for easy dismantling to permit tube cleaning.

MANUFACTURER'S FIELD SERVICES

Prepare and start systems under provisions of Section [01600.] [01650.]

Supply service of factory trained representative for a period of [_____] days to supervise testing, dehydration and charging of machine, start-up, and instruction on operation and maintenance to Owner.

Supply initial charge of refrigerant and oil.

DEMONSTRATION

Provide systems demonstration under provisions of Section [01670.] [_____.]

Demonstrate system operation and verify specified performance. Refer to Section 15990.

SCHEDULE

Drawing_Code ACH-1 ACH-2 ACH-3

Location

Manufacturer

Model Number

Cooling Capacity

Evaporator

Water Flow

Entering Water Temperature

Leaving Water Temperature

Pressure Drop

Fouling Factor

Condenser

Entering Air Temperature

Condensing Temperature

Heat Recovery Condenser

Type

Water Flow

Entering Water Temperature

Leaving Water Temperature

Pressure Drop

Fouling Factor

Compressor

Number

Steps Unloading

RPM

Starter Type

END OF SECTION