| 摘要 |
PROBLEM TO BE SOLVED: To elongate the endurance life of an overpressure releasing solenoid valve. SOLUTION: In case that hot water supply and additional stoking are used at the same time, an overpressure releasing solenoid valve 20 is closed. Or, at additional stoking operation, this device is equipped with a control means which opens or closes the overpressure releasing solenoid valve 20 in every specified time when it heats a treat exchange 17 for additional stoking. As a result, the drive time of the overpressure releasing solenoid valve is shortened, and the endurance life rises.
|
