HEAT PUMP HOT WATER HEATER

摘要

A heat pump hot water heater (10) includes a refrigerant circuit (20), a water circuit (30) and a control unit (40). The refrigerant circuit includes a first heat exchanger (21) configured to cause heat exchange between air and refrigerant, a second heat exchanger (25) configured to cause heat exchange between the refrigerant and water, and a compressor (22) configured to compress the refrigerant. The water circuit includes the second heat exchanger and a water supply mechanism (31) configured to supply the water to the second heat exchanger. The control unit is configured to control the refrigerant circuit and the water circuit so as to perform a defrosting operation of the first heat exchanger. The refrigerant circuit is capable of switching between a forward cycle operation and a reverse cycle operation. At least either in starting the defrosting operation or during performing the defrosting operation, the control unit is configured to determine a possibility of freezing of the water in the water circuit and select to perform either the forward cycle operation or the reverse cycle operation so as to perform the defrosting operation.