摘要 |
Upon a call for heat, gas flows to a pilot burner, a spark generating circuit is energized to ignite the pilot burner, and an oscillator is energized. When flame appears, the output signal of the oscillator is effective, through flame responsive means including capacitor means and solid-state switch means, to enable energizing of the primary winding of a coupling transformer at the frequency of the oscillator signal. When so energized, sufficient power transfer occurs between the primary and secondary windings of the coupling transformer to enable energizing of a relay winding, which energizing terminates energizing of the spark generating circuit and allows gas to flow to the main burner.
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