I have a problem with my furnace not igniting. The pressure switch is working fine, but the flame will not stay lit more than a second. I cleaned the flame sensor and checked the gas valve. The light on the circuit board turns off as soon as the flame shuts off, with no flashing at all. The only way to get it to do anything is to reset power on the unit. The breaker is not tripping. Please help, my dogs are freezing and I can't afford to use space heaters all the time.
Sounds like a bad circuit board or faulty ground from it to the furnace and furnace to ground.. Check for ground from the furnace to a copper water line with a cheater wire if necessary. If the board is mounted on a plate on the fan those plates come lose and lose grounding and blow the board. Need to put more sheet metal screws in it to tighten it up. Buy the board from a reputable dealer not Bubba on zbay.
"Cut it twice and it is still too short".