Specifically the Everest Star installed in most
Bigfoot trailers.
I'm no expert, but aside from having once stayed at a Holiday Inn Express, I also pulled mine out, replaced a bunch of parts, put it back in and...eventually it worked.
The disclaimers: this post assumes you are comfortable working with electricity and
propane, a couple of the most-likely-to-kill-you things in your camper. I don't claim to understand all the systems and how they work, but I've always been decent enough at taking parts out and replacing them with new ones.
For someone used to intelligent tinkering, with an understanding of
propane lines and electricity and safety, this is pretty straightforward. For someone stumbling around with very little understanding...pretty dang dangerous. There's a lot you can mess up if you aren't careful. If you aren't comfortable,
don't mess with it. Spend the money and let a pro do it, or find a friend of a friend or whatever who has the experience and let them help you.
I had a
furnace issue recently so I decided to do a bit of a refurbish of mine, replacing the parts that kept coming up as likely-to-fail when I was trouble shooting and searching the internet, and are included in tune-up kits like
this.
This will just be a "how to replace" guide for a few parts, in case someone is searching, and like me, found nothing online. My
furnace was in great shape aside from some failing electronics. If you find a lot of corrosion/rust or anything, it's probably better to just replace the entire
furnace.
Ok, with that out of the way:
The circuit board, limit switch, time delay relay, electrode and most gas-related parts can all be replaced
without removing the furnace. The sail switch, a common failure, cannot. The motor also requires furnace removal.
Furnace removal:
Turn off the gas at the tanks, pull the furnace fuse at the power center. If either of these cause you trouble, go ahead and call it quits and bring it to a service technician
Other than a screwdriver, helpful tools are allen wrenches, adjustable crescent wrenches, and a
good pair of wire crimpers
Unhook the gas line to the furnace. Take out the front screws.
The furnace is now held in only by the exhaust tube sticking in from the outside of the trailer. You can wiggle/pull it out slowly, just until you can see the wires on the opposite side from where the gas connects. Once you can see the wires, cut them. I left enough wire to be able to see what color matches up to what, since they're different.
Now work the furnace all the way out. I think it's a good idea to plug the open gas line in the camper. I also covered the gas connection on the furnace.
Then remove the air intake and exhaust stuff from the outside. Two screws, then the rest just pulls out.
These don't need to come out for servicing, but you'll have a very hard time getting the furnace to line up with them when you try to put it back in. You'll want to install them after you get the furnace back in. I just found it easier to get the leverage I needed to separate them from the furnace by pulling on the furnace itself, rather than these exterior parts.
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