JUMO designed their DIN EN 14597 approved flue gas temperature monitors for usage in electro-mechanical applications. Besides safe operation of heating systems, these temperature monitors can also controll an extraction fan and monitor parallel operated heating boilers. These thermostats function based on the rod length expansion principle. The immersion tube and a metal rod fitted in the tube have different expansion coefficients. When heated, a temperature dependent length difference is produced which triggers the thermostat's switching action.
Edited by: Filip Burm