Community Forums

timmer594 · 03-07-2011, 06:19 PM

I have a Duo Therm gas furnace, blower comes on, I can hear gas valve open, doesn't light. I've tried it numerous times, had air in other gas lines. Got very thing else lit. Can't hear any "clicking" of lighter. I can't seem to figure out how to open it up to get to burner it is under my buffet seating. Any help?
Thanks

TXiceman · 03-07-2011, 07:08 PM

If you hear the gas valve open, it should have DSI, direct spark ignition, You should heat the ignitor sparking. If the voltage is low, you may not be getting the sail switch to clear signaling that the air is flowing.

If it is an older furnace, it may have a standing pilot which you have to manually light. But you should not be hearing the gas valve open if the pilot is not lite.

On the heater cover, there should be some instructions.

Let us know the brand and model.

Ken

Haubera · 03-23-2011, 10:49 PM

Two years ago I replaced the sail switch on my DuoTherm as it wouldn't light unless I tapped on the bar holding the sail switch. It was sticking. Last year it wouldn't light again when I was dry camping, and I ended up buying a new battery this spring. It works fine again. So I'd suggest if it won't work when you are hooked up to power, then it's probably the sail switch. If you're somewhat handy you can replace it yourself if it's like mine... I bought the part online for around $40 and put it in myself too (along with new elecrodes for the spark just to make sure).