| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a storage water heater that has an excellent instant hot water supply function and can suppress fluctuation of a temperature of hot water at start of hot water supply.SOLUTION: A storage water heater includes a heat pump unit 1, a hot water storage tank 11, hot water delivery piping 13, water supply piping 14, water supply branch piping 15, 16, a hot water supply mixing valve 17, hot water supply outgoing piping 19, hot water supply return piping 21, a circulation pump 23, tank return piping 24, a flow passage change-over valve 25 and the like. In a heat insulating circulation operation, partial hot water A of circulating hot water is made to flow in to the hot water storage tank 11 to mix high temperature water A' taken out from the hot water storage tank 11 with residual hot water B by the hot water supply mixing valve 17, so as to generate intermediate temperature water C, and the intermediate temperature water C is circulated. At this time, a mixing ratio between the high temperature water A' and the hot water B by using the hot water supply mixing valve 17 is set to be a ratio between 0% and 100%. Thus this can avoid direct supply of the high temperature water in the hot water storage tank 11 at start of hot water supply.</p> |
