SUGGESTED SPECIFICATION
The HEAT PUMP shall be A. O. Smith Model AHPA-25 having a heating capacity capable of 27,450 BTU/h and cooling capacity of 21,200 BTU/h.
The HEAT PUMP shall have a scroll compressor, factory charged with R134a refrigerant, NSF61-approved stainless steel circulator pump, and double-wall stainless steel condenser for potable water applications. The HEAT PUMP shall have a factory coated evaporator coil. The complete heat pump assembly shall carry a one (1) year limited warranty.
The HEAT PUMP refrigerant circuit shall contain an adjustable thermal expansion valve, receiver, accumulator, serviceable filter drier and service ports for refrigerant gauges.
The HEAT PUMP shall be certified and listed by TUV to CSA C22.2 No. 236:2015, UL 1995:2015-07 standards. The HEAT PUMP shall be certified for indoor and/or outdoor installation.
The HEAT PUMP shall be constructed with a heavy gauge aluminum jacket assembly and painted on both sides.
The HEAT PUMP shall utilize a 24 VDC control circuit and components. The control system shall have a display (PLC Option) for HEAT PUMP set-up, HEAT PUMP status and HEAT PUMP diagnostics. All components shall be easily accessed and serviceable. The HEAT PUMP shall be equipped with low and high refrigerant pressure switches short-cycle control outlet water temperature sensor and return water temperature sensor.
The HEAT PUMP shall have an optional control for “Cascade” to sequence and rotate while maintaining operation of up to eight HEAT PUMPs of same BTU inputs.
The HEAT PUMP shall be capable of controlling a valve (single pass option) that maintains constant delivery temperature to the storage tank. The HEAT PUMP shall have an optional gateway device which will allow integration with BACnet.
The HEAT PUMP shall be equipped with terminal strips for electrical connections. A low voltage connection board shall have connection points for safety and operating controls, i.e., alarm contacts, runtime contacts and tank thermostat. A high voltage terminal strip shall be provided for supply voltage connection. Supply voltage shall be 208-230V/1PH/60Hz, 208-230V/3PH/60Hz, 440-480V/3PH/60Hz, or 575V/3PH/60Hz.
The HEAT PUMP shall be suitable for use with polypropylene glycol, up to 50% concentration. The de-rate associated with the glycol will vary per glycol manufacturer.
STANDARD CONSTRUCTION
The HEAT PUMP shall be constructed in accordance with the code requirements as standard equipment.
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