Abstract: A control system for an automatic damper in a heat generation system. The damper is provided with a spring biasing arrangement to open the damper when the plant is generating heat to permit unobstructed discharge of the products of heat generation. A motor maintains the damper closed when no heat is being generated. Provision is made for disabling the control system permitting the damper to be opened by the spring and the heat generator to function normally when a malfunction occurs in a switch which normally performs in a safety capacity. Included in this arrangement is a fuse in a circuit which opens the circuit when the switch fails as the result of a short circuit or welding of the contacts. The circuit includes means for preventing short circuiting during normal operation.