RV Furnace Smells Like Propane: What You Need To Do

As an RVgoer, you know that one of the essential parts of your vehicle is the RV furnace. It keeps you warm and cozy during long drives and nights spent camping. Unfortunately, sometimes the furnace can have problems that result in strange smells. If you suddenly notice a smell of propane in your RV, it could be coming from your furnace.

Your furnace, when working correctly, should still give you fresh air and excellent indoor air quality. Any odor or smell is a sign that something is not working correctly and should be investigated as soon as possible.

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RV Furnace Smell

It’s not a pleasant smell, but at least propane has that distinct odor that allows us to determine if there is a leak.

Propane is a colorless and odorless gas that, when left alone, can be dangerous. But propane suppliers add a chemical called Odorant-Mercaptan to help alert people if the gas starts to leak. This chemical gives the gas an unpleasant smell that you may have noticed before.

If you suspect that the propane smell is coming from your furnace, it is time to investigate because you have either a furnace or a propane problem.

Where is that Smell

First, your best bet is to investigate where the propane smell comes from. Since propane is a gas, the odor can move around, and it may not be coming from exactly where you may think. This means the smell could come from the propane tank, down to any part of the gas line.

If you want to investigate your entire propane system, visit this post on finding a gas leak if you smell propane outside your RV.

Propane Leak Detector

Propane leak detectors come in various shapes and sizes and can be easily installed in the RV furnace. They work by continuously monitoring the air within the furnace for any traces of propane gas or other combustible vapors.

Propane Leak Detector at Amazon.com

When these vapors are detected above a predetermined threshold, the alarm is activated. This allows you to take action before any potential danger arises from an undetected gas leak.

Causes of Leak

If the propane is coming from your furnace, there are multiple areas that you will need to check out for the smell.

Gas Line

Like any propane appliance in your RV, it will be connected to a gas line. Remember, your camper is bouncing and going down a highway at high speed. Any connection, including your propane line, is in jeopardy of getting loose over time.

Check the connection. See if there is any corrosion or debris that may cause an issue.

Check the tightness of the nut ferrule. Give it a slight turn with a wrench to see if it tightens and removes the odor. Since sometimes it is difficult to tell my smell alone, use the soapy water method in the link noted above. By seeing the bubbles in the water, it will let you know that gas is escaping and the likely culprit of the leak.

Incomplete Combustion

The furnace heat exchanger works by safely combusting fuel to generate warmth. This process occurs in a combustion chamber that’s sealed off from the living area of the RV. The hot air produced within this chamber then passes through a metal plate called a ‘heat exchanger.’ This plate absorbs the heat before directing it into the interior of the RV via ducts or vents.

If there is any issue with your furnace and the heat exchanger is giving you incomplete combustion, some of the propane could be leaking out of the furnace. Another concern with incomplete combustion is that the furnace could produce carbon monoxide. If enough CO2 is given off, your RV carbon monoxide detector will warn you. If that is the case, get out to fresh air as soon as possible and get to a furnace repair person.


Besides the issues above, another source of the smell could be your exhaust. Any disruption in the exhaust could put back into your RV unwanted odors or propane gas.

The exhaust system for an RV furnace works much like a car’s exhaust system. The purpose is to provide ventilation and prevent dangerous gases such as carbon monoxide from entering your RV. The exhaust pipe runs from the back of the furnace outside, usually through a wall or vent into the atmosphere. This ensures that no hazardous materials are emitted inside your living space.

Use compressed air to clear out the heater exhaust.

Check your exhaust for any clogs or debris inside. Sometimes rodents can get inside and create a mess that causes damage. You can also use compressed air to blow out any obstructions that find their way inside the vent.

Final Thoughts

What’s that smell I smell! That is what my son used to say when he was two years old and smelled something out of the ordinary. If you are in your RV and the furnace is giving off a propane smell, that is something you want to pay attention to.

First, you learned that you need to investigate the source of the leak to make sure it is indeed the furnace. Secondly, check gas line connections to ensure they are tight and leak-free. Finally, make sure your exhaust vent is free and clear, and no debris is backing up the ability to get rid of the odor gases.