Abstract: A gas valve device includes an integral drip leg and filter, positioned upstream from valve means contained therein, for collecting and removing liquid and solid impurities from a gas stream. The drip leg and filter includes a fine-mesh screen of significantly larger cross-sectional area than an inlet opening through which the gas stream enters the gas valve device. The screen is positioned at an angle to cause solid particles to be deflected away from the screen. Clean-out means is located between the inlet opening and the screen for collecting and removing the accumulated liquid and solid impurities. In a preferred embodiment, a detachable cover can be removed to enable cleaning or replacing the screen.

Abstract: In a gas burner control system a normally closed, electromagnetically opened first valve has primary control of gas flow to pilot and main burners and the application of gas pressure to cause a normally closed, diaphragm-operated second valve controlling gas flow to a main burner to open; the first valve opens and a spark igniter becomes operative to ignite the pilot upon closure of a space thermostat. A thermostatically operated switch heated by pilot flame has a cold position through which a circuit to open the first valve is completed and a hot position through which a circuit causing the diaphragm-operated second valve to open is completed. A holding circuit paralleling the switch is effective to hold the first valve open when the switch moves to its hot position, but is ineffective to open it, so that upon failure of the electrical power supply, the first primary control valve will not open until the switch has cooled to its cold position.

Abstract: A gas burner control system in which closure of a space thermostat causes energization of an electromagnetic actuator to supply fuel to a pilot burner and effect the operation of an igniter to ignite it; a thermostatic actuator heated by the pilot flame then effects the flow of fuel to a main burner where it is ignited by the pilot burner. The electromagnetic actuator also jointly controls the flow of fuel to the main burner, so that when the thermostat opens, de-energizing the electromagnetic actuator, fuel flow to the main burner as well as to the pilot burner is immediately cut off.