| 摘要 |
<P>PROBLEM TO BE SOLVED: To sufficiently shorten a starting time of a heat pump water heater. <P>SOLUTION: In a case when a temperature variation determining means S3 determines that the difference between a water inlet temperature Twi as a hot-water supply temperature at an inlet side of a water passage of a water-refrigerant heat exchanger and a tank water temperature Twb as a hot-water supply temperature near a hot-water supply outlet of a hot water storage tank is the predetermined first standard difference KTd1 or more, and a temperature variation state in which the water inlet temperature Twi can be changed, may exist immediately after the start of the heat pump cycle, before starting the heat pump cycle of the heat pump water heater, an electric water pump of a water circulating circuit is operated until a temperature stabilization determining means S6 determines the transfer to a temperature stabilization state in which the difference between the water inlet temperature Twi and the tank water temperature Twb is the predetermined second standard difference KTd2 or less. Thus the water inlet temperature Twi can quickly approach the tank water temperature Twb, and an operating state of a heat pump cycle component device can be properly decided in starting the heat pump cycle. <P>COPYRIGHT: (C)2010,JPO&INPIT |
