| 摘要 |
PURPOSE:To prevent damage due to the action of straight pressure by supplying the forward-side piping system side of a circulating path, to which a circulating pump and sensors such as a pressure sensor are not installed, with hot water at the time of the initial stage of automatic hot-water supply, detecting the state of the flow rate of hot water and controlling the opening and closing of a solenoid valve for automatic hot-water supply. CONSTITUTION:The outlet A of a three-way valve 8 is connected positively to the forward-side piping system 31 of a circulating path at the time of the initial stage of automatic hot-water supply. Consequently, hot water from a heat exchanger 2 for supplying hot water by the opening of a solenoid valve 5 for automatic hot-water supply is fed from the forward-side piping system 31 of the circulating path, to which a circulating pump 7 and sensors such as a pressure sensor 10 are not mounted. Accordingly, straight pressure does not work to the circulating pump 7 and the sensors such as the pressure sensor 10 set up to the return-side piping system 32 of the circulating path even when the piping systems 200A, 200B of a circulating path 200 are brought to a closed state due to freezing, etc., thus positively preventing the damage of these circulating pump 7 and the sensors such as the pressure sensor 10. |
