THERMOMAT® for heat fluid systems Design Control The flow safety device is a very important element as it measures and monitors the minimum heat carrier flow rate and shuts down and interlocks the firing system if the flow rate drops below the minimum value. The safety temperature limiters in the outlet and flue gas prevent an inadmissible rise o the outlet and flue gas temperature. Fuel All commercial gaseous or liquid fuels can be fired, e.g. heavy oil, medium oil, high speed diesel, Bio diesel, liquid gas, natural gas, bio gas. Equipment The controls and safety elements of the THERMOMAT® are comply with the stringent regulations enforced in European Community and DIN 4754.