All right, I'm at my wit's end and I could use some help... Last week my furnace started blowing cold air. The pilot lights fine, but the burners will not light. My ex-wife's boyfriend's friend came out and looked at it and suggested we replace the furnace, said the heat exchanger/combustion chamber was bad, and said the thermostat was bad, too. I replaced the thermostat, and that didn't fix the problem. I posted another post and asked what else could be wrong - when I connect a 24v line from the transformer directly to the gas valve, the valve opens and the burners ignite. I figured out the wiring schematic and figured it was something electrical, not the valve or anything, so I diagnosed the two temperature sensors/switches (one was a snap disc temperature limit switch and the other was the fan/limit switch), and replaced them (they both seemed to be stuck open). I hooked everything back up, lit the pilot, and... nothing. The valve doesn't open and the burners don't try to ignite. I'm out of ideas. What else could it be? The unit is an OLD GE unit that I can't find any info on it, but I'm not going to replace the furnace, as I'll be moving in a month and can't afford to. Please help! Thanks in advance!