| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat source device for preventing degradation in a heating heat exchanger when shifting from an individual operation of a hot water supply operation or a heating operation to simultaneous operation of the hot water supply operation and the heating operation.SOLUTION: A controller 20 controls a combustion amount of a hot water supply burner 4-1 by hot water supply capacity switching valves 43L, 43M, 43S and a gas proportional valve 42 so that a temperature of hot water supplied from a hot water supply pipe 8b may become a target hot water supply temperature, and also controls a combustion amount of a heating burner 4-2 by heating capacity switching valves 44L and 44S so that a temperature of hot water sent out from a heating heat exchanger 3-2 to a heating circulation circuit 9 may approach a target heating supply temperature during simultaneous operation of a hot water supply operation and a heating operation, and starts combustion of the heating burner 4-2 in a state of making a combustion range of the heating burner 4-2 smaller than the maximum combustion range by the heating capacity switching valves 44L and 44S when shifting from an individual operation of the hot water supply operation or the heating operation to the simultaneous operation of the hot water supply operation and the heating operation. |
