| 摘要 |
PURPOSE:To obtain suitable hot-water temperature from the beginning of operating a heater not to generate after-boiling, by keeping the circulating water temperature constant by circulating water flow in a bypass pie having a pump for circulating the water flow between a heat exchanger outlet side and inlet side and having a check valve therein. CONSTITUTION:When hot-water temperature is set, then a pump 24 is operated and a circuit for circulating between a water flow switch 15, a heat exchanger 16 and a hot-water temperature detector 17 is organized. The circulating water is heated by a burner 19, the hot-water temperature is detected by the hot-water temperature detector 17, and the temperature of the circulating water is kept constant. In case of heating according to a set temperature the burner 19 is used, and in case of cooling an exhaust fan 21 is used. When a hot water supply tap 27 is opened, a bypass pipe 26 is closed by a check valve 25 and desired hot- water supply temperature is readily obtained because an instantaneous heater 13 interior is already arranged at a set temperature. When the hot-water supply tap 27 is closed, the circulating circuit is formed again not to generate after-boiling. |
