| 摘要 |
PURPOSE:To enlarge the utilizable supply hot water temperature level and to reduce radiated heat loss by closing a circulating circuit by a control valve at the time of supplying hot water and stopping the circulation. CONSTITUTION:When hot water is supplied by the opening of a supply hot water taps 22 or 23, a control circuit 26 adjusts the mixing ratio of hot water from a supply hot water heat source apparatus 12 and a supply water bypass pipe 18 so that hot water assumes a temperature set by a temperature setter 24 or 25 by a hot water-water mixing valve (control valve) 17. In this case, since a supply hot water return pipe 14 is closed by the mixing valve 17, hot water circulated from the supply hot water return pipe 14 does not mix in water during the hot water supply. When the hot water supply taps 22 and 23 are closed, the flow quantities of flow quantity sensors 20 and 21 become zero. By detecting it, the mixing valve 17 is switched, the bypass supply water pipe 18 is closed, and hot water from the supply hot water heat source apparatus 12 is circulated from a supply hot water feed pipe 13 through the supply hot water return pipe 14 by a circulating pump 15 which has been started simultaneously. |
