Flue gas sensor + thermocouple De Dietrich 97939003

This combined flue gas sensor and thermocouple assembly is essential for monitoring exhaust conditions and flame presence in boilers and gas burners. The flue gas sensor measures temperature or composition to optimize combustion efficiency, while the thermocouple provides a safety shutoff if the pilot flame goes out. Together, they help reduce emissions, improve fuel economy, and prevent dangerous gas leaks. Over time, these sensors can degrade due to soot buildup or thermal cycling, leading to inaccurate readings or system lockouts. Replacing this assembly restores proper combustion control and safety functionality. A vital spare part for heating equipment maintenance and repair.