Trane SEN0355 Flame Sensor

The Trane SEN0355 is an essential safety accessory for Trane gas-fired furnaces and boilers. It is a flame sensor and informs whether there is a flame in the burner assembly or not. This sensor or though a photodiode or some other light sensing component, intensity of ultraviolet light emitted during combustion is measured. The sensor picks up UV light when the flame is burning properly and sends a signal to the control board that all is well. However, the sensor does not sense the UV light and initiates a safety shutdown process if the flame extinguishes or ignites in a wrong manner. It prevents accumulation of unburned gas in the system which may cause explosion or poisoning by carbon monoxide.