Getting a bit cool out there? RV owners turn to their furnace when the sun goes down in the spring, fall and winter. The RV can still be a comfortable place to stay without the need for a hotel, if your furnace is working properly.
Like any other household appliance that provides heat or cold, furnaces can develop issues. We are here to provide some advice on what to look for when your furnace keeps turning off and on.
RV owners will want to check several things if the furnace keeps turning on and off. These include vents, supply lines for gas, and your thermostat. We’ll explain each potential problem in more detail.

Checking your RV furnace vents
We suggest checking your RV furnace vents because problems within your RV furnace vents are the easiest issue to fix. They also represent a potential safety hazard if blocked.
Your furnace will have a vent that reaches outside to intake fresh air. Ensure this vent is not blocked by boxes, debris, dust, or anything else. A lack of intake air can lead to the furnace cycling on and off.
This is also an opportune time to clean the vents in general, even if they aren’t the problem. Very dusty vents can reduce the air quality in your RV and the efficiency of your furnace.
Exhaust vents on the outside
Check the exterior exhaust vents too. If these are plugged, the furnace could overheat when it does run and shut off. These could be packed with anything from animals like spiders and birds to whatever outside could possibly fit in the vent. If it’s cold out, the exhaust vent should have some steam coming out when the furnace is on.
If you don’t see steam or any water remnants, the vent is likely plugged.
Look into the vent with a flashlight to see any obstructions. You might want to wear some disposable gloves and goggles before putting any body parts into the vent port. Who knows what will come out. Have a trash bag ready, too!
Thermostat
Most RV thermostats have just a couple functions – measure the temperature of the indoor air near the thermostat and trigger the furnace and AC to turn off or on.

Thermostats can indeed break. They can send signals at the wrong time, not send at all, or read the air temperature wrong.
If the vents for your furnace look good, this could be the easiest first step for you to take. Other options include looking deeper into the equipment for your furnace.
If the thermostat is reading the indoor air temperature incorrectly, it can repeatedly turn the furnace on and off at inappropriate times. If you adjust the thermostat up and down for a higher temperature, and it still shuts off, the thermostat could be an issue.
The thermostat is also one of the easiest things to replace. We can’t give specific instructions, but generally removing the thermostat from the wall just involves a screwdriver. You’ll want to look at how the wires connect and probably consult the instructions within a new thermostat you purchase.
Furnace Interior Problems
Both high efficiency and non-high efficiency furnaces can be a bit complicated. Modern furnaces often have computer and circuit boards that help regulate flow. These circuit boards can indeed become problematic and cause the furnace to stop and start.
Computer boards are replaceable, though they can be complicated and we’d recommend professional help. They often have many connections that need to be in the right spot.
An issue with the furnace computer boards will be harder for you to detect, Most technicians will plug tools into the board to see if electricity and signals are flowing right, and most people don’t have the tools in their RV to check this ability.
Propane flow
Most RV furnaces are powered by combustible propane. A lack of propane flow will cause the furnace to shut down or stop producing heat.

Ensure that your propane lines are clean and flowing. Naturally, your propane tank also needs propane inside. If your propane is running low or out, it can’t send the needed amount for heating your RV.
Regular maintenance
Maintaining your RV furnace every year is an easy way to prevent having an issue with the furnace turning on and off. A technician can see signs that parts on the furnace are wearing out, in addition to ensuring it’s clean enough to operate normally.
Use a vacuum on your vent ports on a regular basis to do a hands off approach without having to actively tough potentially gross amounts of dust
Timing
It’s actually possible that your furnace intends to turn on and off every few minutes. With a working thermostat, the RV could simply be losing enough heat for the furnace to need to turn on every few minutes to retain heat.
This issue is more likely when the RV is not well insulated and the weather outside is especially cold – or if your thermostat is turned up rather high.
Check your RV to see where heat is flowing out of. This can be done by examining the outside of your RV with the heat on, and feeling for warm spots.
The best way to solve this is adding more insulation to your RV, plugging up holes, or keeping the thermostat temperature lower.
RV owners might experience the same problem mid summer when the AC is on, making this something that can be prevented year round.
Conclusion
There are many reasons why your RV furnace might be stopping and starting. We suggest starting with the fixes that could be easiest, like checking vents and the thermostat before moving into technical parts.
Especially for off the grid campers and those camping in colder areas, yearly maintenance will help prevent issues.
So keep yourself warm during the cool season and check things out ahead to ensure you have heat when you want it.