236200-AIR_TO_WATER_HEAT_PUMPS_A02.pdf

Sitka Ranger District Office Renovation Sitka, Alaska 100% Construction Documents May 23, 2014

SECTION 236200 – PACKAGES COMPRESSOR AND CONDESNOR UNITS

PART 1 - GENERAL

1.1 SYSTEM DESCRIPTION

A. System consists of an air-to-water heat pump employing the standard reverse-Rankin cycle with R-410A as the refrigerant. With inverter controlled compressor to extract heat from the outdoor air and transfers the heat through brazed plate (cupro-nickel) heat exchanger. Also contains water circulating pump, auxiliary heater, and controls.

B. Three heat pumps shall be operated to back-up the primary biomass boiler system.

1.2 FEATURES

A. Compressor - capacity shall be modulated automatically to maintain a constant suction pressure, while varying the refrigerant volume for the needs of the heating loads.

B. VFD Inverter Control - Each unit shall use a high efficiency, variable speed “inverter” compressor coupled with inverter fan motors and electronic expansion valve for superior part load performance.

C. Advanced Diagnostics - Systems shall include a self-diagnostic, auto-check function to detect a malfunction and display the type and location.

D. (Cupro-Nickel) brazed plate heat exchanger.

1.3 QUALITY ASSURANCE

A. The units shall be tested by a Nationally Recognized Testing Laboratory (NRTL), in accordance with ANSI/UL 1995 Heat and Cooling Equipment and (ETL) Electrical Laboratories and bear the listed mark.

B. All wiring shall be in accordance with the National Electric Code (NEC).

C. The system will be produced in an ISO 9001 and ISO 14001 facility, which are standards set by the International Standard Organization (ISO). The system shall be factory tested for safety and function.

D. Mechanical equipment for wind-born debris regions shall be designed in accordance with ASCE 7-2002 and installed to resist the wind pressures on the equipment and the supports.

E. The outdoor unit will be factory charged with R410A

1.4 DELIVERY, STORAGE, AND HANDLING

A. Unit shall be stored and handled according to the manufacturer’s recommendations.

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AG-0116-S-14-0021

Amendment 002

PART 2 - PRODUCTS

2.1 OUTDOOR UNIT

A. General:

1. The outdoor unit shall be factory assembled and pre-wired with all necessary electronic and refrigerant controls. The refrigeration circuit of the outdoor unit shall consist of scroll compressors, motors, electronic expansion valves, solenoid valves, 4-way valve, distribution headers, capillaries, filters, shut off valves, oil separators, service ports and liquid receivers.

2. The system will automatically restart operation after a power failure and will not cause any settings to be lost, thus eliminating the need for reprogramming.

3. The condensing unit shall be modular in design and shall allow for side-by-side installation with minimum spacing.

4. The following safety devices shall be included: high pressure switch, control circuit fuses, crankcase heaters, fusible plug, high pressure switch, overload relay, inverter overload protector, thermal protectors for compressor and fan motors, over current protection for the inverter and anti-recycling timers.

B. Unit Cabinet:

1. The outdoor unit shall be completely weatherproof and corrosion resistant. The unit shall be constructed from rust-proofed mild steel panels coated with a baked enamel finish

C. Outdoor Coil:

1. The outdoor coil shall be manufactured from copper tubes expanded into aluminum fins to form a mechanical bond.

2. The heat exchanger coil shall be of a waffle louver fin and rifled bore tube design to ensure high efficiency performance.

3. The heat exchanger on the outdoor units shall be manufactured from Hi-X seamless copper tube with N-shape internal grooves mechanically bonded on to aluminum fins to an e- Pass Design.

4. The fins are to be covered with an anti-corrosion acrylic resin and hydrophilic film type E1.

5. The pipe plates shall be treated with powdered polyester resin for corrosion prevention.

The thickness of the coating must be between 2.0 to 3.0 microns.

D. Compressor:

1. The inverter compressors shall be variable speed (PAM inverter) controlled which is capable of changing the speed to follow the variations in total heating load as determined by the suction gas pressure as measured in the condensing unit. In addition, samplings of evaporator and outdoor temperatures shall be made so that the high/low pressures detected are read every 20 seconds and calculated. With each reading, the compressor capacity shall be controlled to eliminate deviation from target value.

2. The capacity control range shall be 23% to 100%.

3. Each compressor shall be equipped with a crankcase heater, high pressure safety switch, and internal thermal overload protector.

4. The compressor shall be spring mounted to avoid the transmission of vibration.

E. Electrical:

PACKAGED COMPRESSOR AND CONDENSOR UNITS 236200 - 2

1. The power supply to the outdoor unit shall be 208/230volts, 1 phase, 60Hz+/- 10%.

2.2 WARRANTY

A. The units shall have five (5) years for parts from date of installation. The units shall have a limited labor warranty for a period of one (1) year from date of installation. The compressors shall have a warranty of seven (7) years from date of installation.

2.3 INSTALLTION REQUIREMENTS

A. The system must be installed by a manufacturer trained contractor/dealer. The bidders shall be required to submit training certification proof with bid documents.

2.4 PERFORMANCE

A. EBLQ/EDLQ - Outdoor unit shall perform as indicated below.

Heating Capacity (Btu/h)

Cooling Capacity (Btu/h)

Power Input Heating (Watts)

Power Input Cooling (Watts)

COP

EER

54,600 -- 3,930 -- 4.07 --

1. Measuring Conditions:

a. Heating Ta DB/WB 44.6°F/42.8°F (7°/6°C) – LWC 95°F (35°C) (DT=9°F (5°C)

Cooling Ta 95°F (35°C) - LWE 64.4°F (18°C) (DT=9°F (5°C)

2. Ambient Operating Range

a. Heating (Min./Max.): -4/95°F (-20/35°C)

PART 3 - EXECUTION

3.1 INSTALLATION

A. Install units with adequate clearances for service and maintenance. Provide sufficient clearances around fans for access and servicing of components. Install fans such that tachometer openings, access doors, motors, belts, lubrication lines, electrical connections, etc.

are readily accessible and not obstructed by other installations or structures. Tighten electrical connectors and terminals according to manufacturer's published torque-tightening values. If manufacturer's torque values are not indicated, use those specified in UL 486A and UL 486B.

B. No field installation work shall be required for Refrigerant Piping Line Sets or Refrigerant Charging.

C. The minimum required water flow for the indoor unit operation is 5.3 gallons/min (20 L/min).

D. Units shall be controlled with staging controller per sequence and be setup as backup devices designed to stage in to meet the backup setpoint of the hot water storage tank. Signal shall come from DDC which is monitoring the storage tank temperatures.

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3.2 CLEANING

A. On completion of installation, internally clean system according to manufacturer's written instructions. Remove foreign material and construction debris.

B. After completing system installation, including outlet fitting and devices, inspect exposed finish.

Remove burrs, dirt, and construction debris and repair damaged finishes.

END OF SECTION 236200

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