| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress the lowering of a temperature of high temperature water in an upper part in a hot water storage tank as much as possible, and to perform the freezing prevention operation of a heat-pump heating circuit, in a heating device for circulating and heating hot water in the hot water storage tank in a heat pump unit and using the hot water for heating of a heater. <P>SOLUTION: A heat-pump heating circulation circuit 4 includes: a water intake port 8 communicating with the lower part in the hot water storage tank 2; an upper hot water supply port 13 communicating with the upper part in the hot water storage tank 2; a lower hot water supply port 9 communicating with the lower part of the hot water storage tank 2; a heat-pump heating and circulating pump 10; and a flow passage changeover valve 14. The heating device executes hot water storage operation for operating the heat pump unit 3 and the heat-pump heating and circulating pump 10 to send hot water to the upper hot water supply port 9 by the flow passage changeover valve 14 and freezing prevention operation for operating the heat-pump heating and circulating pump 10 with the heat pump 3 stopped to send hot water to the lower hot water supply port 13 by the flow passage changeover valve 14. <P>COPYRIGHT: (C)2010,JPO&INPIT |
