Furnace problem

I've not had a chance to go to where we have the camper to do any work on it. Our last football game (I coach) is Saturday and hopefully I'll get some time to go work on it.
My furnace is installed without an access door so at best I can check the high temp cut off, which is closed as it should be. I can remove the exterior vent cover and see what I can get to before removing the unit.
There is an access door I could install and I may do this to make future servicing easier.

I had a furnace problem a few years ago. I was told by the dealer that there are 3 switches on the furnace and one was malfunctioning and they replaced the regulator at the propane tank. Whether the regulator needed to be changed or not I have no idea I was at their mercy..??

do you have bug screening over the intake louvers? Is so, try running it with the outside cover off to see if the bug screen is restricting air flow. Otherwise, as others have said, blow out the air tube on the outside of the trailer and look for any obstructions (e.g. mud dauber nest)

Almost all the std. stuff that goes wrong with furnace is fixable without pulling it.

You should be able to blow out the furnace without removing it. Pick up a couple cans of computer air and give it a try.
Parts breakdown may help on locating sail switch
SF parts breakdown
Here is service manual
SF service manual

You're right it is a suburban. Great ideas on repair and they make sense. I'll pull the furnace and do the checks. The camper is in storage about 30 minutes from work and I plan on pulling it when I go over to check on the camper.
Thanks to those who have helped!!!
Jim

I would open the furnace up and give it a good blow with compressed air. Locate the sail switch and blow it off good.

Sounds like a sail switch has gone bad. My heater, when turned on, would blow for about 15 seconds, then stop. No heat, just the blower.

I checked on line and suspected the sail switch. I called a tech and he confirmed the problem, saying it is common. New sail switch and voila, it worked.

I used mine only once the spring I bought it, then that fall it would not light on our second trip. The dealer took out the furnace and took it apart and it was full of RUST! Yep, the first time we'd used it, it had burned the paint off of the inside which contributed to the rust and dust inside it. He used an air hose to blow it out, re-assembled it and it has worked fine ever since. Says he gets at least 10-12 every fall for the same thing. When fan kicks on, it will not light and time out. You can hear it trying to light but had sounded like it had very low pressure, not the forceful 'swoosh' you normally hear when trying to light. It's because it is blowing around so much rust/dust particles.

That would be a Suburban 30,000 btu furnace. Mine was full of toasted bugs. The first time it happened I was able to clean most of it out by putting a good shop vac in blower mode and blowing thru the inlet, then the outlet, alternating until no more came out. The second time I had to remove the furnace and give it a better cleaning.