Section 15662 AIR COOLED RECIPROCATING CHILLER

Section 15662

AIR COOLED RECIPROCATING CHILLER

PART 1 - GENERAL

1.1 THE REQUIREMENT A. Section Includes:

1. Air cooled reciprocating chiller.

B. Related Specification sections include but are not necessarily limited to:

1. Division 01, Additional General Requirements

2. Section 11005, Equipment: Basic Requirements

3. Section 15970, Instrumentation and Control for HVAC systems.

4. Section 15954, HVAC Testing, Adjusting and Balancing

5. Section 16220, Electric Motors

6. Section 16442, Control Panels

1.2 QUALITY ASSURANCE

A. Referenced Standards:

1. Air Movement and Control Association (AMCA).

2. Air Conditioning and Refrigeration Institute (ARI).

3. American Society of Heating, Refrigerating and Air Conditioning Engineers

(ASHRAE):

HVAC Applications Handbook, Chapter entitled "Sound and Vibration Control."

20 Methods of Testing for Rating Remote Mechanical-Draft

Air-Cooled Refrigerant Condensers.

52.2, Method of Testing General Ventilation Air-Cleaning

Devices for Removal Efficiency by Particle Size

4. Canadian Standards Association (CSA).

5. National Electrical Manufacturers Association (NEMA):

250 Enclosures for Electrical Equipment (1000 Volts

Maximum)

6. National Fire Protection Association (NFPA):

70 National Electrical Code (NEC).

7. American Society of Mechanical Engineers (ASME).

8. National Roofing Contractors Association (NRCA).

9. Building code:

a. International Code Council (ICC):

International Building Code and associated standards, 2009 Edition including all State of California 2010 amendments, referred to herein as California Building Code.

B. Miscellaneous:

1. Gauge thickness specified herein shall be manufacturer's standard gauge for steel and Brown and Sharpe gauge for non-ferrous metals.

2. Corrosion protection of equipment to be as specified herein.

1.3 SUBMITTALS

A. Shop Drawings:

1. Wiring diagrams.

2. Control diagrams. B. Product Data.

C. Contract Closeout Information:

1. Operating and maintenance data.

2. OCSD instruction report.

3. Test reports.

PART 2 - PRODUCTS

2.1 CHILLER(S)

A. Acceptable manufacturers:

1. Chiller(s): a. Trane. b. Carrier.

c. Or Equal.

B. Chiller(s): Electric motor driven semi-hermetic reciprocating liquid chiller unit with compressor(s), evaporator, condenser(s), capacity control and controller, motor starter(s), instrument and control panel and other items as indicated.

1. Capacity: As scheduled on Drawings.

2. Coated with chlorinated vinyl lacquer.

3. Jack screws for leveling.

4. Isolation under compressor(s).

5. Complete initial charge of refrigerant and oil.

6. Relief valve(s) on condenser(s).

7. Flow switch.

8. Controls as indicated.

9. 115V convenience outlet, fused.

10. 1/4 inch welded steel frame with 14 and 12 gauge casing and access doors.

11. Coil guards.

12. 5-year complete compressor warranty. C. Condenser: Dual Circuited, Vertical Coils:

1. Aluminum fins mechanically bonded to 5/8 inch OD copper tubes.

2. Sub-cooler circuit with liquid accumulator.

3. Test at 425 PSIG air.

4. Belt driven, vertical discharge fans.

a. Statically and dynamically balanced.

5. Three phase motors.

a. Permanently lubricated ball bearings. b. 3 phase thermal overload protection.

D. Compressor(s): Direct drive, Semi-hermetic Reciprocating Compressor(s):

1. Electric actuated cylinder head unloading.

2. Oil pump and strainer.

3. Immersible crankcase heater.

4. Suction and discharge shutoff valves.

5. Motor cooled by suction gas.

E. Driving Motor:

1. Maximum Input: As scheduled on Drawings.

2. Suction gas cooled.

3. Input at full load shall not exceed nameplate rating.

4. Provide motor with over-temperature protection.

5. Motor: As specified in Section 16220, Electric Motors. .

F. Cooler: ASME Code, Stamped:

1. Water Side Working Pressure: 150 PSIG.

2. Shell and tube type.

3. Tubes individually replaceable, rolled into tube sheets.

4. Copper water tubes.

5. Insulation with vapor retarder on cooler.

G. Refrigerant Circuits: 2 Independent Circuits, Each with Following:

1. Thermal expansion valve.

2. Filter-drier.

3. Liquid line sight glass.

4. Sound attenuation.

5. Charging port with valve.

6. Insulated suction line.

7. Liquid line solenoid valve.

8. Full operating charge of refrigerant.

2.2 TEMPERATURE CONTROLS A. Control Devices:

1. Flow Switch: Furnish 120 V electric single pole, single throw flow switch with wiring diagram.

2. Sequence Panel: Furnish a microelectronic master sequence panel, remote flow sensor and custom wiring diagram.

3. Devices integral with chiller.

a. Packaged controls for control of chiller. Include but not limited to following:

1) Weather-tight enclosure with separate sections for refrigeration and electrical controls.

2) Part winding starters.

3) Non-cycling compressor overloads.

4) High and low oil pressure cut out switches.

5) Reset relay.

6) Compressor service switches.

7) Motor protector.

8) Central Unit Microprocessor, with Following Functions: Compressor anti- recycle function. Compressor lead-lag. Low water temperature cut out. Loss of charge protection. Leaving chilled water temperature control. Load limiting.

9) Unit mounted main fused disconnect switch for single point electrical connection.

10) Cycle counter and hour meter for each compressor.

11) Gauge board with manual shutoff to monitor discharge, suction and oil pressure (1 set per circuit).

12) Control transformer (120 V). B. Sequence of Operation:

1. Flow proven by remote mounted chilled water flow switches.

2. Master sequence panel senses leaving water temperature and rate of temperature change over time to control chilled water loop temperature.

3. Master sequence panel overrides individual chiller sequence controls, leaving safety controls intact.

4. When sensor temperature is outside of control band (adjustable), master sequencer will load or unload unit compressors to maintain 45 degree (adjustable) setpoint.

5. Master sequencer will not add or subtract a stage when rate of temperature change exceeds 1.5 degrees F per minute, regardless of water temperature.

6. Master sequencer employs a parallel alternate loading control scheme.

PART 3 - EXECUTION

3.1 INSTALLATION

A. Install as indicated and in accord with manufacturer's instructions and recommendations.