Originally posted by: Rubycon
Glowcoil ignitors have this safeguard because they are susceptible to burnout and/or damage. What's scary are stoves with standing pilots with no FSG on the pilot feed! So when the pilot is blown out by a draft from the unfortunate homeowner leaving with the door slamming, the house fills slowly with gas.
If they are lucky and not gone long and there's a window open, they'll arrive to a smelly kitchen and (hopefully) know what's up. If they're not so lucky and gone longer allowing the gas to build up and reach another appliance with a standing pilot such as a water heater, things can and do go BOOM!
If they're really unlucky, the worst scenario is there's no other source of ignition until they've arrived home - turn on the lights, and the spark of the switch touches off an explosion giving them along with the house - the new look. :Q
Don't screw with gas and it won't screw with you.