The Raypak interrupted proved ignition device conserves energy. When additional heat is needed, the combustion air blower starts to purge all air from the combustion chamber for about 15 seconds. On proof of air flow, the air proving switch closes and the igniter is energized, eliminating the fuel costs of maintaining a constant pilot. To assure safe operation, the gas valve cannot open until the pilot igniter is verified. The 100% igniter safety is an electronic device which closes the main gas valve within 8/10 of a second whenever the flame is interrupted. Main burner is automatically lit when the device is powered and pre-purged. Unit performs its own safety check and opens the main valve only after the igniter is proven to be capable of ignition.