OR and 204 Chiller Specs.pdf

03-01-20

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SECTION 23 64 00

PACKAGED WATER CHILLERS

PART 1 - GENERAL

1.1 DESCRIPTION

A. This section covers Rotary-Screw

B. Rotary-Screw

1.2 RELATED WORK

A. Section 00 72 00, GENERAL CONDITIONS.

B. Section 01 00 00, GENERAL REQUIREMENTS.

C. Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, and SAMPLES.

D. Section 01 91 00, GENERAL COMMISSIONING REQUIREMENTS

E. Section 11 41 21, WALK-IN COOLERS and FREEZERS.

F. Section 13 05 41, SEISMIC RESTRAINT REQUIREMENTS FOR NON-STRUCTURAL

COMPONENTS.

G. Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION.

H. Section 23 05 12, GENERAL MOTOR REQUIREMENTS FOR HVAC and STEAM

GENERATION EQUIPMENT.

I. Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and

EQUIPMENT.

J. Section 23 08 00, COMMISSIONING OF HVAC SYSTEMS.

K. Section 23 21 13, HYDRONIC PIPING.

L. Section 23 21 23, HYDRONIC PUMPS.

M. Section 23 23 00, REFRIGERANT PIPING.

N. Section 23 31 00, HVAC DUCTS and CASINGS

O. Section 23 81 00, DECENTRALIZED UNITARY HVAC EQUIPMENT.

P. Section 26 29 11, LOW-VOLTAGE MOTOR STARTERS.

1.3 DEFINITION

A. Engineering Control Center (ECC): The centralized control point for the intelligent control network. The ECC comprises of personal computer and connected devices to form a single workstation.

B. BACNET: Building Automation Control Network Protocol, ASHRAE Standard

135.

C. Ethernet: A trademark for a system for exchanging messages between computers on a local area network using coaxial, fiber optic, or twisted-pair cables.

D. FTT-10: Echelon Transmitter-Free Topology Transceiver.

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1.4 QUALITY ASSURANCE

A. Refer to Paragraph, QUALITY ASSURANCE, in Section 23 05 11, COMMON WORK

RESULTS FOR HVAC and STEAM GENERATION, and comply with the following.

B. Refer to PART 3 herein after and Section 01 00 00, GENERAL REQUIREMENTS for test performance.

C. Comply with AHRI requirements for testing and certification of the chillers.

D. Refer to paragraph, WARRANTY, Section 00 72 00, GENERAL CONDITIONS, except as noted below:

1. Provide a 5-year motor, transmission, and compressor warranty to include materials, parts and labor.

E. Refer to OSHA 29 CFR 1910.95(a) and (b) for Occupational Noise Exposure

Standard

G. Refer to ASHRAE Standard 15, Safety Standard for Refrigeration System, for refrigerant vapor detectors and monitor.

1.5 APPLICABLE PUBLICATIONS

A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only.

B. Air Conditioning, Heating and Refrigeration Institute (AHRI):

370-current ........... Sound Rating of Large Outdoor Refrigerating and

Air-Conditioning Equipment

495-current ........... Refrigerant Liquid Receivers

550/590-current........ Standard for Water Chilling Packages Using the

Vapor Compression Cycle

560-current ........... Absorption Water Chilling and Water Heating

Packages

575-current ........... Methods for Measuring Machinery Sound within

Equipment Space

C. American Society of Heating, Refrigerating, and Air-Conditioning

Engineers (ASHRAE):

15-current ............ Safety Standard for Mechanical Refrigeration

Systems

GDL 3-current ......... Guidelines for Reducing Emission of Halogenated

Refrigerants in Refrigeration and Air-

Conditioning Equipment and Systems

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D. American Society of Mechanical Engineers (ASME):

CFVC VIII-1 current ... ASME Boiler and Pressure Vessel Code, Section

VIII, "Pressure Vessels - Division 1"

E. American Society of Testing Materials (ASTM):

C 534/C534M-current .... Preformed, Flexible Elastomeric Cellular

Thermal Insulation in Sheet and Tubular Form

C 612-current ......... Mineral-fiber Block and Board Thermal

Insulation

F. National Electrical Manufacturing Association (NEMA):

250-current ........... Enclosures for Electrical Equipment (1000 Volts

Maximum)

G. National Fire Protection Association (NFPA):

70-current ............ National Electrical Code

H. Underwriters Laboratories, Inc. (UL):

1995-current .......... Heating and Cooling Equipment

1.6 SUBMITTALS

A. Submit in accordance with Specification Section 01 33 23, SHOP

DRAWINGS, PRODUCT DATA, and SAMPLES.

B. Manufacturer's Literature and Data.

1. Rotary-screw and/or scroll, control panels, and vibration isolators, and remote condenser data shall include the following:

a. Rated capacity.

b. Pressure drop.

c. Efficiency at full load and part load WITHOUT applying any tolerance indicated in the AHRI 550/590/Standard.

d. Refrigerant

e. Fan performance (Air-Cooled Chillers only.)

f. Accessories.

g. Installation instructions.

h. Start up procedures.

i. Wiring diagrams, including factor-installed and field-installed wiring.

j. Sound/Noise data report. Manufacturer shall provide sound ratings. Noise warning labels shall be posted on equipment.

k. Refrigerant vapor detectors and monitors.

C. Maintenance and operating manuals for each piece of equipment in accordance with Section 01 00 00, GENERAL REQUIREMENTS.

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D. Run test report for all chillers.

E. Product Certificate: Signed by chiller manufacturer certifying that chillers furnished comply with AHRI requirements. The test report shall include calibrated curves, calibration records, and data sheets for the instrumentation used in factory tests.

PART 2 - PRODUCTS

2.1 ROTARY-SCREW AND SCROLL AIR-COOLED WATER CHILLERS

A. General: Factory-assembled and-tested rotary-screw or scroll water chillers, complete with evaporator, compressors, motor, starters, integral, and controls mounted on a welded steel base. The chiller unit shall consist of two compressors minimum, but not more than eight, mounted on a single welded steel base. Where compressors are paralleled, not more than two shall be so connected and not less than two independent refrigerant circuits shall be provided. Chiller shall be capable of operating one of the following refrigerants: HCFC-134a or

HCFC-410a.

B. Performance: Provide the capacity as shown on the drawings. Part load and full load efficiency ratings of the chiller shall not exceed those shown on the drawings.

C. Capacity of a single air-cooled chiller shall not exceed 250 Tons

(Standard AHRI Conditions).

D. Applicable Standard: Chillers shall be rated and certified according to

AHRI 550/590, and shall be stamped in compliance with AHRI certification.

E. Acoustics: Sound pressure levels shall not exceed the following specified levels. The manufacturer shall provide sound treatment if required to comply with the specified maximum levels. Testing shall be in accordance with AHRI requirements.

OCTAVE BAND Overall

63 125 250 500 1000 2000 4000 8000 dB(A)

101 102 98 97 96 91 86 83 100

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F. Compressor (Rotary-Screw Type): Positive-displacement oil injected type, direct drive, cast-iron casing, precision-machined for minimum clearance about periphery of rotors. Lubrication system shall provide oil at proper temperature to all moving parts. Capacity control shall be by means of single slide valve to modulate the capacity from 100 to

30 percent of full unit rated capacity and hot gas bypass without unstable compressor operation. The slide valve shall be hydraulically operated upon the actuation of temperature or pressure sensor.

G. Compressor (Scroll Type): Three dimensional, positive-displacement, hermetically sealed design, with suction and discharge valves, crankcase oil heater and suction strainer. Compressor shall be mounted on vibration isolators. Rotating parts shall be factory balanced.

Lubrication system shall consist of reversible, positive displacement pump, strainer, oil level sight glass, and oil charging valve. Capacity control shall be by on-off compressor cycling of single and multiple compressors and hot gas bypass .

H. Refrigerants Circuit: Each circuit shall contain include an expansion valve, refrigerant charging connections, hot-gas muffler, compressor suction and discharge shutoff valves, replaceable-core filter drier, sight glass with moisture indicator, liquid-line solenoid valve and insulated suction line.

I. Refrigerant and Oil: Sufficient volume of dehydrated refrigerant and lubricating oil shall be provided to permit maximum unit capacity operation before and during tests. Replace refrigerant charge lost during the warranty period, due to equipment failure, without cost to the Government.

J. Condenser:

1. Air-cooled integral condenser as shown on the drawings and specified hereinafter.

K. Evaporator: Shell and tube design with seamless copper tubes roller expanded into tube sheets. Designed, tested, and stamped in accordance with applicable portions of ASME Boiler and Pressure Vessel Code, Section VIII, for working pressure produced by the water system, but not less than 1035 kPa (15 psig). Refrigerant side working pressure shall comply with ASHRAE Standard 15. Shell shall be constructed of

23 64 00 - 6 carbon steel. For the waterside of liquid cooler the performance shall be based on a water velocity not less than 1 m/s (3 fps) with a maximum water velocity of 3 m/s (10 fps) and a fouling factor 0.0000176 m2 degrees C (0.0001 hr. sq. ft.) degrees F/Btu. Brazed plate and frame type heat exchanger design. Brazed plate evaporator shall be constructed of stainless steel with copper brazing material. The evaporator shall be designed for a minimum of 1.5 times the working pressure produced by the water system, but not less than 10,350 kPa

(150 psig). Refrigerant side working pressure shall comply with ASHRAE

Standard 15. Evaporator for packaged air-cooled chiller units designed for outdoor installation shall be protected against freeze-up in ambient temperature down to -30 degrees C (-20 degrees F) by a resistance heater cable under insulation with thermostat set to operate below 3 degrees C (37 degrees F) ambient. If electric resistance heater is required and the chiller is connected to emergency power, provide emergency power to the heater cable.

L. Insulation: Evaporator, suction piping, compressor, and all other parts subject to condensation shall be insulated with 20 mm (0.75 inch) minimum thickness of flexible-elastomeric thermal insulation, complying with ASTM C534.

M. Refrigerant Receiver: Provide a liquid receiver for chiller units when system refrigerant charge exceeds 80 percent of condenser refrigerant volume. Liquid receivers shall be horizontal-type, designed, fitted, and rated in conformance with AHRI 495. Receiver shall be constructed and tested in conformance with Section VIII D1 of the ASME Boiler and

Pressure Vessel Code. Each receiver shall have a storage capacity not less than 20 percent in excess of that required for fully charged system. Each receiver shall be equipped with inlet, outlet drop pipes, drain plug, purging valve, and relief devices as required by ASHRAE

Standard 15.

N. Controls: Chiller shall be furnished with unit mounted, stand-alone, microprocessor-based controls in NEMA 4 enclosure, hinged and lockable, factory wired with a single point power connection and separate control circuit. The control panel provide chiller operation, including monitoring of sensors and actuators, and shall be furnished with light emitting diodes or liquid-crystal display keypad.

1. Following shall display as a minimum on the panel:

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a. Date and time.

b. Outdoor air temperature.

c. Operating and alarm status.

d. Entering and leaving water temperature-chilled water and condenser water.

e. Operating set points-temperature and pressure.

f. Refrigerant temperature and pressure.

g. Operating hours.

h. Number of starts.

i. Current limit set point.

j. Maximum motor amperage (percent).

2. Control Functions:

a. Manual or automatic startup and shutdown time schedule.

b. Condenser water temperature.

c. Entering and leaving chilled water temperature and control set points.

d. Automatic lead-lag switch.

3. Safety Functions: Following conditions shall shut down the chiller and require manual reset to start:

a. Loss of chilled water flow.

b. Loss of condenser water flow (for water-cooled chillers only).

c. Low chilled water temperature.

d. Compressor motor current-overload protection.

e. Freeze protection (for air-cooled chillers).

f. Starter fault.

g. High or low oil pressure.

h. Recycling pumpdown.

O. The chiller control panel shall provide leaving chilled water temperature reset based on signal from Energy Control Center (ECC).

P. Provide contacts for remote start/stop, alarm for abnormal operation or shutdown, and for Engineering Control Center (ECC) .

Q. Chiller control panel shall either reside on the "BACnet network", and provide data using BACnet standard network variable types and configuration properties, or BACnet interworking using ARCNET or MS/TP physical data link layer protocol for communication with building automation control system.

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R. Auxiliary hydronic system and the chiller(s) shall be interlocked to provide time delay and start sequencing as indicated on control drawings.

S. Motor: Refer to Section 23 05 11, COMMON WORK RESULTS FOR HVAC and

STEAM GENERATION. Compressor motor furnished with the chiller shall be in accordance with the chiller manufacturer and the electrical specification Section 23 05 12, GENERAL MOTOR REQUIREMENTS FOR HVAC and

STEAM GENERATION EQUIPMENT. Starting torque of motors shall be suitable for driven machines.

2.4 CONDENSING UNITS FOR AIR CONDITIONING SERVICE

Refer to Section 23 81 00 DECENTRALIZED UNITARY HVAC EQUIPMENT.

2.5 CONDENSERS

A. Air-Cooled Condensers: Suitable for remote installation in a weather-protected casing. For multiple compressors chiller units, provide a separate air-cooled condenser to match the compressor:

1. Condenser coils shall be extended surface fin and tube type, seamless copper tubes with aluminum fins. See Paragraph 2.7 below for corrosion protection

2. Fans shall be either housed-centrifugal or plenum or propeller type as best suited for application, directly connected to motor shaft or indirectly connected to motor by means of a V-belt drive. Fans shall be statically and dynamically balanced.

3. Discharge air from each air-cooled condenser in vertical direction either directly from fan casing or by means of supplementary wind deflectors.

4. Condenser Controls: Provide head pressure controls for operation of the system down to 5 degrees C (40 degrees F) by cycling the fans.

B. Refrigerant Piping: Refrigerant piping shall be as specified in specification Section 23 23 00, REFRIGERANT PIPING.

2.6 REFRIGERANT MONITORING AND SAFETY EQUIPMENT

A. General: Provide refrigerant monitoring sensor/alarm system and safety equipment as specified here. Refrigerant sensor and alarm system shall comply with ASHRAE Standard 15. The refrigerant monitoring system will be provided by the chiller manufacturer and shall be interfaced with the DDC control system.

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B. Refrigerant monitor shall continuously display the specific gas

(refrigerant used) concentration; shall be capable of indicating, alarming and shutting down equipment; and automatically activating ventilation system. On leak detection by refrigerant sensor(s), the following shall occur:

1. Activate machinery (chiller) room ventilation.

2. Activate visual and audio alarm inside and outside of machinery room, with beacon light(s) and horn sounds equipment room and outside equipment room door(s). Shut down combustion process where combustion equipment is employed in the machinery room.

3. Notify Engineering Control Center (ECC) of the alarm condition.

C. Refrigerant monitor shall be capable of detecting concentration of 1 part per million (ppm) for low-level detection and for insuring the safety of operators. It shall be supplied factory-calibrated for the apparent refrigerant.

D. Monitor design and construction shall be compatible with temperature, humidity, barometric pressure, and voltage fluctuations of the machinery room operating environment.

2.7 CORROSION PROTECTION

A. Remote Outdoor Condenser Coils: Epoxy Immersion Coating – Electrically

Deposited: The multi-stage corrosion-resistant coating application comprises of cleaning (heated alkaline immersion bath) and reverse-osmosis immersion rinse prior to the start of the coating process. The coating thickness shall be maintained between 0.6-mil and 1.2-mil.

Before the coils are subjected to high-temperature oven cure, they are treated to permeate immersion rinse and spray. Where the coils are subject to UV exposure, UV protection spray treatment comprising of UV-resistant urethane mastic topcoat shall be applied. Provide complete coating process traceability for each coil and minimum five years of limited warranty. The coating process shall be such that uniform coating thickness is maintained at the fin edges. The quality control shall be maintained by ensuring compliance to the applicable ASTM

Standards for the following:

1. Salt Spray Resistance (Minimum 6,000 Hours)

2. Humidity Resistance (Minimum 1,000 Hours)

3. Water Immersion (Minimum 260 Hours)

4. Cross-Hatch Adhesion (Minimum 4B-5B Rating)

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5. Impact Resistance (Up to 160 Inch/Pound)

B. Exposed Outdoor Cabinet: Casing Surfaces (Exterior and Interior): All exposed and accessible metal surfaces shall be protected with a water-reducible acrylic with stainless steel pigment spray-applied over the manufacturer’s standard finish. The spray coating thickness shall be

2-4 mils and provide minimum salt-spray resistance of 1,000 hours (ASTM

B117) AND 500 hours UV resistance (ASTM D4587)

PART 3 – EXECUTION

3.1 EXAMINATION

A. Examine roughing-in for concrete equipment bases, anchor-bolt sizes and locations, piping and electrical to verify actual locations and sizes before chiller installation and other conditions that might affect chiller performance, maintenance, and operation. Equipment locations shown on drawings are approximate. Determine exact locations before proceeding with installation.

3.2 EQUIPMENT INSTALLATION

A. Install chiller on concrete base with isolation pads or vibration isolators.

1. Concrete base is specified in Section 03 30 00, CAST-IN-PLACE

CONCRETE

2. Vibration isolator types and installation requirements are specified in Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and

EQUIPMENT

3. Anchor chiller to concrete base according to manufacturer’s written instructions and for seismic restraint on vibration isolators.

4. Charge the chiller with refrigerant, if not factory charged.

5. Install accessories and any other equipment furnished loose by the manufacturer, including remote starter, remote control panel, and remote flow switches, according to the manufacturer written instructions and electrical requirements.

6. Chillers shall be installed in a manner as to provide easy access for tube pull and removal of compressor and motors etc.

B. Install refrigerant monitoring and safety equipment in accordance with

ASHRAE Standard 15.

C. Install refrigerant piping as specified in Section 23 23 00, REFRIGERANT PIPING and ASHRAE Standard 15.

D. Install thermometers and gages as recommended by the manufacturer and/or as shown on drawings.

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E. Piping Connections:

1. Make piping connections to the chiller for chilled water, condenser water, and other connections as necessary for proper operation and maintenance of the equipment.

2. Make equipment connections with flanges and couplings for easy removal and replacement of equipment from the equipment room.

3. Extend vent piping from the relief valve, rupture disk, and purge system to the outside.

3.3 STARTUP AND TESTING

A. Engage manufacturer's factory-trained representative to perform startup and testing service.

B. Inspect, equipment installation, including field-assembled components, and piping and electrical connections.

C. After complete installation startup checks, according to the manufacturers written instructions, do the following to demonstrate to the COR that the equipment operate and perform as intended.

1. Check refrigerant charge is sufficient and chiller has been tested for refrigerant leak.

2. Check bearing lubrication and oil levels.

3. Verify proper motor rotation.

4. Verify pumps associated with chillers are installed and operational.

5. Verify thermometers and gages are installed.

6. Verify purge system, if installed, is functional and relief piping is routed outdoor.

7. Operate chiller for run-in-period in accordance with the manufacturer’s instruction and observe its performance.

8. Check and record refrigerant pressure, water flow, water temperature, and power consumption of the chiller.

9. Test and adjust all controls and safeties. Replace or correct all malfunctioning controls, safeties and equipment as soon as possible to avoid any delay in the use of the equipment.

10. Prepare a written report outlining the results of tests and inspections, and submit it to the COR.

D. Engage manufacturer’s certified factory trained representative to provide training for 16 hours for the VA maintenance and operational personnel to adjust, operate and maintain equipment, including self-contained breathing apparatus.

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E. The Commissioning Agent will observe startup and contractor testing of selected equipment. Coordinate the startup and contractor testing schedules with the COR and Commissioning Agent. Provide a minimum of 7 days prior notice.

F. Provide services of manufacturer’s technical representative for four hours to instruct VA personnel in operation and maintenance of computer room air conditioning equipment.

3.4 COMMISSIONING

A. Provide commissioning documentation in accordance with the requirements of Section 01 91 00 GENERAL COMMISSIONING REQUIREMENTS and Section 23

08 00 – COMMISSIONING OF HVAC SYSTEMS for all inspection, start up, and contractor testing required above and required by the System Readiness

Checklist provided by the Commissioning Agent.

B. Components provided under this section of the specification will be tested as part of a larger system. Refer to Section 23 08 00 –

COMMISSIONING OF HVAC SYSTEMS and related sections for contractor responsibilities for system commissioning.

3.5 DEMONSTRATION AND TRAINING

A. Provide services of manufacturer’s technical representative for four hours to instruct VA personnel in operation and maintenance of units.

Coordinate this training with that of the cooling tower, if furnished together.

B. Submit training plans and instructor qualifications in accordance with the requirements of Section 23 08 00 – COMMISSIONING OF HVAC SYSTEMS.

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