No-heat furnace fixed!

Recently I posted a question from RVtravel.com reader, Rick, who had little or no heat coming out of his RV’s furnace. In the original post I suggested checking the ductwork, sail switch, or burner assembly. I very seldom get a follow-up; however, Rick did send back this initial response.

Rick’s initial response

Dave, thanks for this troubleshooting procedure.

I’ve checked that all the ducts/hoses are connected and free of kinks/obstructions.

Can the sail switch be checked without removing the entire furnace assembly from the motorhome? Not sure if I want to tackle that; we’re on the road now and I don’t have a shop with a bench, nor a bunch of tools with me!

If the sail switch is indeed dirty and not “sailing” to the correct position to keep the burner ignited, would the heat output when the burner first ignites at least be hot, then cool down to just warm air as the sail switch sinks?

As I said in the description of the problem, it doesn’t even start out hot.

The furnace is 15 years old; never been serviced. I’ve seen a few YouTube videos where the problem was that the burner was completely rusted out, with holes in the mesh portion.

Maybe it’s this? Replacing the burner looks fairly simple with the tools that I have onboard.

Thanks for your quick response to my issue. —Rick

My response

If it is not getting hot initially, then I would replace the burner assembly as it most likely is rusted, as you indicated. Plus it seems to be more accessible for you. —Dave

Then, today, the fix!

Hello David,
Replacing the burner was fairly straightforward; I also replaced the igniter probes. The spade terminal connector was fairly rusty and there was a slight, small crack in the insulator at the base. Fired it up and it is hot again… Yay!

I certainly appreciate what you and others do to help us RVers keep our rigs running! Your channel is especially good; clear and easy to follow tips. Fingers crossed I won’t have to look you up again in the near future, but, with a 15-year-old rig with quite a few of the original systems still working, one never knows!

Thanks again for your help with this. I’ll pay it forward next time I see another RVer out there staring at their non-working furnace.

I attached a photo of the burner; it didn’t look that bad. —Rick

 You might also enjoy these posts from Dave 

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• Why won’t RV’s furnace work when camping but works for service tech?
• Why does RV furnace light on second attempt but not first?
• Furnace airflow issue follow-up with photos

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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