Manual Heat Pump Model HHPM-V.2- SEP 2012
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air temperature falls, so does heat pump capacity and efficiency. The minimum entering air temperature
should not lower than 15C as the heat pump capacity is less than half of the rating.
The maximum leaving water temperature that can be produced by any heat pump water heater is
determined by the maximum allowable pressure of the refrigerant. The heat pump uses environmentaily
friendly R134a refrigerant which operates at lower pressures than R22. Heat Pump can produce leaving hot
water temperatures up to 65C.
Notice that average hot water storage tank temperature sensed by the aquastat bulb will be lower
than the water temperature leaving the heat pump. This means that the practical aquastat setpoint will be
between 55 and 60C.
2.3 Water Quality
The method of describing water quality is Total Dissolved Solids, TDS, in ppm. In broad terms:
a)
100 ppm or less TDS = good Quality drinking water
b)
500 ppm TDS = marginally drinkable water
c)
1200 ppm TDS = considered "brackish" water
The Heat Pump Water Heater (condensers) are stainless steel plate type heat exchanger to
transfer heat from the condensing R134a refrigerant to water. The Heat Pump with stainless steel
condensers should operate acceptably with water having up to 1200 ppm TDS provided no deposit clog in
the channel between plates.
Cleaning the condensers is necessary when scale is found. Scale removal shall be done through
the drain and vent connection installed outside of the unit. Flushing with water before get back to operation
to avoid chemical drain into the hot water system.
2.4 Equipment Sizing
Proper selection and sizing of the heat pumps is determined by several factors including:
Size of the storage tank.
Supply water temperature.
Hot water temperature(tank).
Total daily volume of hot water.
Usage pattern (load profile).
Inlet air temperature and humidity.
Contact Energy Master Co., Ltd or representative to correctly size the heat pumps and storage
