If the blower comes on its not the thermostat.?
But it could be a whole bunch of other things.? Some potential problems:
1. The sail switch, which senses that the blower is on, is defective
2. The battery is low so the blower doesn't blow hard enough
3. The exhaust outlet is blocked so the sail switch won't trigger
4. The igniter is bad or dirty and won't light the propane
5. The sensor that determines the propane is lit and hot fails.
6. The propane jet is clogged so the flame either won't light or burns too low.? If the jet is clogged you?
? ? ?probably need to blow out the propane lines too.? One person on this site replaced the whole furnace
? ? ?but the problem still didn't go away.? Clogged lines suck.
7. The controller board is bad.
For a DWYer you might get it fixed in a day, or might spend weeks ordering parts until you find the culprit.? Or you could take it to an RV place and they'll fix it in an hour or two, but that will cost some $$$.
