I'm on the road currently, 3k miles in from NH to Colorado. Nights are dropping below freezing and the furnace will turn on the blower based on thermostat settings, but the burner isn't lighting. The unit is a duotherm with an electrically lit pilot, and I have the gas valve open near the unit. The fridge and stove work fine off propane. The house battery is at 12V-- I even tried running the furnace when plugged into city power but it still didn't light.
I took one trip a month ago where the furnace worked fine.
What else can I do to troubleshoot and isolate the problem? What does your furnace sound like? Do you hear the distinct popping of the igniter? Do you think it could be a failed solenoid or igniter? How can I confirm? Thanks!