| 摘要 |
PURPOSE:To prevent shortage of hot water by outputting a hot water replacement command when the temperature of hot water in a hot water storage tank used only for storing the hot water is lower than that of replacement reference hot water. CONSTITUTION:A first hot water storage tank is formed as a hot water heating and storing tank provided with a heating means comprising a hot water supplying heat exchanger 14. Second and third hot water storage tanks 12, 13 are formed as exclusive hot water storage tanks having no heating means. The detecting temperature T5 of a fifth temperature sensor 35 attached to the bottom part of the third hot water storage tank 13 is compared with a transfer start setting temperature (replacement reference hot water storage temperature) (Ds-alpha). When T5 is lower than (Ds-alpha), a transfer operation is carried out. Hot water is transferred from the first hot water storage tank 11 whose temperature is higher than thermostatic control setting temperature Doff to the second and third hot water storage tanks 12, 13. A heating operation and a transfer operation are repeated and high temperature hot water substantially higher than the thermostatic setting temperature Doff is stored in all the hot water storage tanks 11 to 13. |
