| 摘要 |
PROBLEM TO BE SOLVED: To prevent freezing of a circulation circuit for connecting a water side of a water heat exchanger and a hot water storage tank.SOLUTION: A heat pump hot water storage type water heater includes: a hot water storage tank unit 2 including a refrigerant temperature sensor 22 for detecting temperature of a refrigerant circulating in a water heat exchanger 19, an inflow water temperature sensor 20 for detecting temperature of hot water flowing on an upstream side of the water heat exchanger 19 of a circulation circuit 17 and a boiling temperature sensor 21 for detecting temperature of the hot water flowing on the downstream side of the water heat exchanger 19 of the circulation circuit 17; and control means 38, 39 for controlling an operation of a circulation pump 18, a compressor 29 and expansion means 31 based on the refrigerant temperature detected by the refrigerant temperature sensor 22, the incoming water temperature detected by the inflow water temperature sensor 20 and boiling temperature detected by the boiling temperature sensor 21. In the hot water storage tank unit 2, a heat exchange unit 27 is provided which can exchange heat by bringing a refrigerant outlet pipe 24 into contact with the circulation circuit 17 on the further upstream side than the inflow water temperature sensor 20. |
