Burner control system

摘要

A burner control system for a hot water boiler is responsive to both outlet water temperature and return water temperature to provide a relatively constant outlet water temperature regardless of variations in heat output requirements. A first thermistor responsive to return water temperature is effective to provide on-off control of gas flow to the burner. A second thermistor responsive to outlet water temperature is effective to vary the rate of gas flow to the burner so as to maintain a predetermined outlet water temperature. A timing circuit is effective each time the burner is turned on to delay a high rate of gas flow to the burner.