DutchmenSport wrote:
Here's another thought? Are you in temperatures below freezing right now? If so, it's possible your propane gas line could have frozen up, perhaps at the regulator. And for anyone who says gas lines don't freeze have never live in Indiana where it happens quite often at people's homes and in RV's. Almost always, the gas meter at home gets frozen. On RV's it's often the regulator.
I'm just saying. .... check it out and make sure you have gas flow. Turn on your gas stove and make sure you have a good flame. If so ... I'll then get off my soap box.
You often see meters frozen and regulators frozen in Indiana? I'm up here in MN and have NEVER seen a meter freeze up. I have seen water in propane supply piping freeze, it is rare. I've used a 20 lb. propane cylinder on the outside of my fish house for 40 years and have not once had a frozen regulator.
Nothing wrong with checking for adequate gas flow by using the stove top burners. Leaving a couple "on" while firing the furnace can sometimes visually show a failing regulator.
The OP does state that the furnace "runs for a few seconds". Whether that means a flame is present hasn't been stated.