| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot water heating device that includes a structure capable of securely sensing closing failure of a low-temperature bypass on-off valve during simultaneous operation of a high-temperature heating terminal and a low-temperature heating terminal, etc.SOLUTION: In a hot water heating device 1, during simultaneous operation of a high-temperature heating terminal 3 and a low-temperature heating terminal 4, a low-temperature bypass on-off valve 18 is opened and a heating temperature by using a heating heat exchanger 2 is controlled to a temperature suitable for the high-temperature heating terminal 3, and for a low-temperature supply passage 12, high-temperature heating water introduced from a high-temperature branch passage 11 and heating water introduced from a low-temperature bypass passage 15 are mixed with each other so as to perform control to a temperature suitable for the low-temperature heating terminal 4. The hot water heating device 1 includes control means that determines whether or not the low-temperature bypass on-off valve 18 is opened after predetermined time has passed since opening control of the low-temperature bypass on-off valve 18 and that changes the heating temperature by using the heating heat exchanger 2 to a temperature lower than that suitable for the high-temperature heating terminal 3 when determining that the low-temperature bypass on-off valve 18 is not opened, during the simultaneous operation. |
