RV Furnace Troubleshooting, Maintenance, and How to Fix Common RV Furnace Issues
- Dec 20, 2025
- 4 min read
Updated: Dec 23, 2025
Cold weather has a way of exposing RV furnace problems fast. What worked fine last season can suddenly start shutting down, burning through propane, or refusing to light when you need it most. A quick search on social media often brings a flood of conflicting advice, with everyone pointing to a different part as the problem. Understanding how your RV furnace works, and what you can safely check as an owner, can save you from unnecessary stress, cold nights, and expensive guesswork.
Understanding Propane Usage and RV Furnace Run Time
RV furnace propane use often causes confusion, especially when colder weather hits or after a furnace upgrade. When tanks seem to empty faster than expected, many RV owners assume something is wrong. In reality, furnace run time comes down to three things, propane tank size, your furnace’s BTU rating, and how many propane appliances are running at the same time. A higher BTU furnace produces more heat, but it will burn propane faster.
Quick Propane Math for RV Owners
Propane weighs about 4.25 lbs per gallon, and one gallon contains about 91,500 BTUs.
To calculate continuous furnace run time:
Tank size in lbs ÷ 4.25 = total gallons
Gallons × 91,500 = total BTUs in the tank
Total BTUs ÷ furnace BTU rating = total run time in hours
Once you understand the numbers, it becomes clear that faster propane use does not automatically mean there’s a problem with your furnace or propane system. Watch the following video to see this math broken down step by step and learn how to calculate how long your RV furnace will run based on BTU rating and propane tank size.
RV Furnace Maintenance Every Owner Needs to Know
When cold weather hits, furnace problems tend to show up fast. Many RV furnace issues aren’t caused by failed parts, they’re the result of dust, pet hair, and restricted airflow that build up while the RV is sitting. When the furnace is finally turned on, all of that debris gets pulled into the system and creates problems right when you need heat the most.
In this video, I walk you through how to find your RV furnace, which is often hidden behind walls, false panels, or interior vents, and how to clean the areas that cause the most trouble. I also explain how airflow affects furnace operation, what can restrict it, and what to check so your furnace can run safely and reliably.
Taking a little time to clean and inspect your furnace before winter can help prevent shutdowns, short cycling, and those cold-weather surprises that turn into emergency calls.
Resources Mentioned in Video:
RV Furnace Sail Switch Troubleshooting
Every winter, the same advice circulates online, replace the sail switch and your furnace will work again. In real RV furnace troubleshooting, what often gets skipped is confirming whether the sail switch is actually the problem.
The sail switch’s job is to verify airflow. If it does not close properly, the furnace will shut down as a safety measure. Dirt, pet hair, dust, or a mechanical failure can all cause the switch to stick or fail, but the symptoms can look identical to several other furnace issues.
In this video, I explain how a sail switch works, how to properly test it with a multimeter, and how to confirm it is truly the failed component before replacing it. Learning proper RV furnace troubleshooting helps prevent unnecessary parts replacement and ensures your furnace operates safely and reliably.
Resources Mentioned in Video:
RV Furnace Circuit Board Troubleshooting
Circuit boards are often blamed when an RV furnace will not start, will not ignite, or shuts down unexpectedly. In many cases, the board is doing exactly what it is supposed to do, responding to another failed component or a loss of proper airflow.
A bad circuit board can prevent the blower motor or igniter from operating, but the only way to know for sure is by testing it correctly. Guessing or swapping boards based on internet advice can waste money and lead to repeat failures.
This video walks you through how to test an RV furnace circuit board with a multimeter, how to follow power flow through the board, and how to tell the difference between a failed board and another issue in the furnace system. Once the problem is confirmed, I show you how to replace the circuit board the right way so the furnace runs safely and reliably again.
Resources Mentioned in Video:
Frequently Asked Questions
Frequently Asked Question #1:
Why does the furnace make a clicking sound but won't turn on?
Frequently Asked Question #2:
Why did all the RV appliances stop working after filling the propane tank?
Frequently Asked Question #3:
Why does the RV furnace run for a few seconds, then stop, without producing heat?
Frequently Asked Question #4:
Why is the RV furnace running but blowing cold air?
When parts get replaced without understanding the root cause, problems tend to come back. Learning what to check first can turn a potential trip-ender into a quick fix.
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About Us
Mobile RV Tech Services specializes in onsite RV repair, maintenance, and inspections. We service your RV at your home, campground, or storage unit in Iosco county in Michigan from April 15 - December 15, and Houston, Texas, from January 1 - April 1.
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