| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a heat pump water heater with a hot water storage tank for storing high temperature hot water even at the lower part with high efficiency without discharge pressure rise of a compressor to make effective use of its capacity, while generating high temperature hot water to be supplied with high efficiency even at a high outside air temperature. <P>SOLUTION: The heat pump hot water supply device comprises a refrigerant circuit having a compressor 31, a radiator 32, a main throttling device 33 and an evaporator 34 connected to one another in sequence. The refrigerant circuit includes a circuit having an on-off valve 38 connected in series to a subsidiary throttling device 39 for bypassing the main throttling device 33 and an auxiliary heat exchanger 40 for heat exchange between refrigerant between the on-off valve 38 and the subsidiary throttling device 39 and refrigerant between the evaporator 34 and the compressor 31. The heat exchange amount of the auxiliary heat exchanger 40 can be increased or reduced and the degree of drying the refrigerant in the inlet of the evaporator 34 and the temperature of suction gas into the compressor 31 can be controlled to control the discharge pressure and temperature of the compressor 31, achieving highly efficient operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
