Patent attributes
According to the required amount of heating, a controller of a combustion apparatus exercises selective on-off switching control on capacity control switching valves for the supplying of gas to three different combustion areas partitioned respectively by a group of three combustion burners, a group of five combustion burners and a group of nine combustion burners, whereby the three combustion areas can selectively be burned, thereby the combustion capacity is changed and switched to any of a plurality of combustion capacity levels. A combustion exhaust temperature sensor is disposed in the vicinity of the inlet of an exhaust stack. Judgment temperatures corresponding respectively to combustion capacity levels for combustion exhaust high-temperature abnormality judgment are set. If the detected combustion exhaust temperature exceeds the judgment temperature corresponding to a current combustion capacity level, this provides a notification indicative of the occurrence of an abnormality while combustion is forcibly stopped.
