Automatic firing (combustion) system

摘要

Automatic firing system for a gas water heater, having an electromagnet which controls a gas valve, a thermal trigger in series with the winding of said electromagnet, a current measuring device for the current flowing through the trigger, and a switched current controller whose actuator is for its part in series with the electromagnet. Provision is made of a monitoring circuit (27) for the switching performance of the regulator (actuator 14). In the event of nonperiodic switching of the controller (21), said circuit firstly switches the latter to the output current of zero and then switches to an output current (13) which is smaller than the pickup current of the electromagnet and larger than the minimum triggering current (14) of the thermal trigger (15). <IMAGE>