Safety guard to overflow associated with the cutting - drawing of an atmospheric burner boiler a

摘要

The invention relates to a back draught security device for the flue breaker (9) of a boiler (1) with an atmospheric burner (3), comprising a control thermostat serving to detect an abnormal rise in temperature, and making it possible in this case rapidly to interrupt the electric supply of the burner, as well as a delay means which allows resetting with a given delay. According to an essential aspect of the invention, the thermostat (150) is arranged against a wall (17) of the flue breaker (9) in order to detect the heating of a predetermined zone of the latter which is greatly stressed in the event of back draught; the thermostat (150) acts directly on the electric supply of the burner (3) when this heating reaches a given threshold, and the delay is ensured by a thermal insulation device (160) arranged against said predetermined zone of the wall in order to slow its cooling, the thermal inertia of this insulation means being selected so that the delay obtained corresponds at least to the given delay time. Application to flue breaker boilers with atmospheric burners. IMAGE