| 摘要 |
PROBLEM TO BE SOLVED: To improve a service life of a combustion appliance by reducing a burner burden by minimizing the frequency of turning on and off combustion operation of a burner. SOLUTION: The combustion appliance comprises a heat exchanger for producing hot water by combustion in a burner, a hot water temperature- measuring device, temperature-setting means, and a controller for controlling combustion operation. Combustion operation of the burner is turned on and off so that a preferable temperature range of hot water is controlled according to a state in use of the combustion appliance. When a measured temperature T of the temperature-measuring device is above a specified temperature in a specified time, the temperature range is enlarged by varying a combustion-off temperature Tof and a combustion-on temperature Ton. After that, when a measured temperature T is not reached to a combustion-off temperature Tof in another certain time, a temperature range after varied is returned to an initial temperature range. Such a control allows frequency of on-off of burner combustion to reduce even at the time of light load with a steep temperature increase.
|
