Heat exchanger control system, control valve device therefor and methods of making the same

摘要

A heat exchanger control system, an electrically operated control valve device therefor and methods of making the same are provided, the heat exchanger control system comprising an electrically operated control valve device having a housing and a differential pressure operated electrical switch unit being operatively interconnected to structure of the system for supplying combustion air to a burner unit of the system and being adapted to be operated thereby to permit the electrically operated control valve device to be operating only when the pressure value of the air being supplied to the burner unit is at or above a predetermined value so that sufficient combustion air will be supplied to the burner unit before the electrically operated control valve device causes fuel to issue from the burner unit, the differential pressure operated switch unit being carried by the housing so as to be self-contained with the electrically operated control valve device.