Patent attributes
A flame detecting system capable of easily performing a deterioration diagnosis of a flame sensor without being provided with a shutter mechanism. The flame detecting system comprising a flame sensor to detect light, a calculating device, and a reference light source, in which the calculating device, by operations of a central processing unit CPU, is configured to execute a first mode at which the discharge probability in the flame sensor is measured when the reference light source is turned off and a second mode at which the discharge probability in the flame sensor is measured when the reference light source is turned on, and calculate a current discharge probability of the flame sensor from data obtained at the first mode and the second mode.
