| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem on freezing of a water heat exchanger disposed in a hot-water heater, in a defrosting operation of an outdoor unit for heat pump-type hot water supply connected with the hot-water heater as a heating system. <P>SOLUTION: This hot-water heater includes the water heat exchanger in which a refrigerant circulated in a refrigerating cycle of the outdoor unit for heat pump-type hot water supply, flows, a water circulation pump for circulating the water exchanging heat with the refrigerant in the water heat exchanger to a heating circuit or a hot water supply circuit, a three-way valve for switching the hot water/water to the heating circuit or the hot water supply circuit, a bypass circuit flowing from a discharge side of the water circulation pump to an inlet side of the water heat exchanger, a first opening/closing valve for controlling the flow of water to the bypass circuit, and a second opening/closing valve for controlling the flow of water to the heating circuit. The three-way valve is switched to a heating circuit side, the first opening/closing valve is opened, and the second opening/closing valve is closed, when the defrosting operation is performed in the outdoor unit for the heat pump-type hot water supply. <P>COPYRIGHT: (C)2013,JPO&INPIT |
