Propane Heater keeps shutting off (7 Fixes)

Your propane heater turns on but keeps shutting off? After reading this article, you will know what to do to fix your propane heater.

I’ve listed the most common causes for your propane heater not staying lit along with an explanation, and a way to test for and fix each cause.

Quick answer: Propane heaters usually keep shutting off and don’t stay lit because of a dirty pilot light or thermocouple. A thorough cleaning of your pilot light with rubbing alcohol and a Q-tip should fix it. Also, ensure your gas line has no kinks and you don’t move it while heating. If this doesn’t work, a triggered safety mechanism such as tip-over protection or overheat protection could be the cause.

Causes and fixes for your propane heater shutting off

The first thing we’re going to look at is your propane heater’s pilot light. This will fix 90% of propane heater issues.

What is a pilot light and how does it work?

A pilot light is a small flame that runs on gas that is branched off the main gas line. The pilot light accomplishes two things:

  • It lights the larger gas line
  • Your heater uses the small pilot light to verify the quality of the flame

Your pilot light is basically the mechanism your heater uses to test the ignition and burn.

The pilot light consists of three main components

  • Pilot light hose
  • Thermocouple
  • Igniter

The pilot light hose is the gas line that supplies the pilot light with gas. A thermocouple is a very simple electric thermometer. And the igniter ignites the gas.

The thermocouple measures the temperature of the gas flame. And only if the gas flame is hot enough, it signals a gas valve to open the main gas line.

mr heater buddy pilot light
This pilot light is too small to reach the thermocouple (sitting opposite the flame)

Vice versa, if the pilot light’s flame is not hot enough, then your propane heater won’t light. Or it might light but it shuts off after some time.

The pilot light is a safety mechanism. If the small pilot light does not burn properly, then your heater assumes that the main heating panels would not burn properly as well.

To save gas and prevent an inefficient burn, the pilot light’s thermocouple shuts down the heating.

What can’t be the cause for your propane heater not staying lit?

Your propane heater does not stay lit and keeps shutting off. There’s one useful piece of information in this sentence: Your propane heater turns on.

This means we can assume (for now) that your propane gas tank and the gas line hose are intact.

Also, we know that your igniter is not the problem.

Also, we know that the initial flame from the pilot light is hot enough to open the main gas line valve. Only after some time does your heater shut off.

So, it is very likely that your pilot light’s flame quality reduces.

Let’s have a look at this first.

1. Pilot light gas opening is clogged

When your pilot light’s gas opening is clogged, the flame coming out of it will not burn properly.

Usually, the reason for this is that you use a large (>20lb) propane tank without a propane gas filter. A filter collects all of the oil coming out of the hose. Lots of gas hoses contain oil (so they ironically don’t clog). 

But after some time, the pressure from your tank pushes the oil into your pilot light’s gas line, where it clogs up.

How to test: Check the gas opening of your propane heater’s pilot light. Touch the inside, or rub it with a Q-tip. Is it greasy? If yes, then you found the issue.

How to fix: Clean the pilot light’s opening with a Q-tip and rubbing alcohol. The alcohol dissolves the grease and helps you remove it.

After a thorough clean, try to run your heater. It should work without shutting off!

If it does not work, continue with the next cause.

2. Thermocouple collects soot

A clean thermocouple is just as important as a clean pilot light. Let’s see what you can do here:

How to test: Turn on your propane heater’s pilot light. Is the flame blue or yellow? If it’s yellow, this indicates a dirty pilot light hose and you should double-check that your pilot light gas line is clean.

If, however, your pilot light’s flame is blue and the flame is large enough to reach the thermocouple, this indicates a faulty thermocouple.

The simplest cause is dirt or soot collecting on your thermocouple. After turning off the propane heater, wipe a handkerchief (or your finger) over the (now cold) thermocouple. Is it dirty?

How to fix: Again, rubbing alcohol is the best solution. Clean the thermocouple with rubbing alcohol and a Q-tip or tissue.

Try running your propane heater. Does it work without shutting off now?

mr heater buddy thermocouple
The thermocouple is the sensor sitting opposite the pilot light flame

3. Thermocouple is broken or has a loose contact

Another potential cure for your propane heater that keeps shutting off could be a broken thermocouple.

The thermocouple is a very simple temperature sensor consisting of just two wires. Normally, they don’t break. But if yours is faulty (for example if it has a loose contact), then it could keep shutting off your propane heater.

How to test: There’s no good test for a broken thermocouple unless you can measure its voltage somehow. There is, however, an easy test for loose contact in a thermocouple.

Before turning on your propane heater, wiggle the thermocouple. Try to run your propane heater.

If its behavior changes after you wiggle it, then a loose contact is a likely reason.

How to fix: If it’s a simple loose contact, try to screw your thermocouple tighter. If that doesn’t help you can buy this replacement thermocouple (click here to view it on amazon). This replacement thermocouple should fit most propane heaters. It is a 30mV thermocouple, so make sure your heater’s thermocouple is 30mV as well.

4. Inconsistent gas pressure

Your propane heater runs on gas. Theoretically, the heating will stop when the gas supply reduces or stop, even if it’s just for a moment.

If your heater does not receive gas even for a second, then the pilot light’s flame shrinks, which reduces the temperature your thermocouple measures. Then, the thermocouple closes the main gas valve.

I suspect that in this case, the main heat should start again once the gas pressure increases again.

However, this depends on how your propane heater is designed.

How to test: Turn your propane heater on. While it’s running, make sure it does not move!

Does it turn off on its own? If it does, then inconsistent gas pressure should not be the reason. However, if it does not turn off, then try moving the gas hose a little. Does it turn off now? If yes, this indicates that your gas hose is sensitive to movement and affects the gas supply.

This often happens when there’s a kink in the hose. In one position, the gas supply works, but when you move the hose a little, the kink closes up the gas and increases the internal hose pressure, which reduces the gas pressure your propane heater receives.

How to fix: Replace your gas hose with a new one.  I would recommend this propane gas hose (click here to view it on amazon).

Please note that this hose is 5 feet in length. If you need a longer hose than that, then select another length (it’s available in different sizes).

5. Tip-over protection activates

Oftentimes, propane heaters have built-in safety mechanisms. That’s not the case for all propane heaters, but I’d say for most.

The issue could be that you turn on your heater and it’s running fine. But only when you move it, it shuts off.

Usually, this is a good thing, since carrying a burning propane heater is not very safe. Also, tip-over protection prevents fires when kids or pets tip over your propane heater.

How to test: Turn on your propane heater. When it’s burning, lift it up and rotate it a bit. You should hear a clicking sound (the tip-over protection triggering) and you see that the heater turns off.

How to fix: Don’t move your heater after turning it on. When you need to move it, turn it off first and only light it at the target location.

6. Propane heater overheats

Another built-in protection mechanism is the overheat protection. Overheat protection shuts a heater off when it overheats.

Propane heaters usually overheat if they stand close to objects that block or reflect the heat.

How to test: Place your propane heater in the middle of the room. No other object should stand close to it. Light the heater and wait for a few minutes. Does it shut off?

What happens if you place your propane heater facing toward a stone wall? Does it shut off then?

If your propane heater shuts off after you move other objects closer to it, then overheating is likely.

How to fix: You can fix your propane heater overheating by placing it in a spot free of obstructions. The heater should face away from the walls and into the room.

7. Heater’s main gas line is clogged

This one is the worst case. If your propane heater still shuts off by itself, even though you tried all of the fixes listed above, then the issue is very likely somewhere in the main gas line.

How to test: Perform all of the fixes listed in this article. Run your propane heater. Does it keep shutting off?

If yes, then a clogged main gas line could be the cause. Your propane heater initially lights, but after some time, it stops working. This could be because the dirt and grease in your heater’s gas line accumulate in one spot with increasing running time.

Your propane heater initially lights up because the grease settled. After turning your heater on, the oil, grease, and dirt take some time to clog up the gas line.

How to fix: To fix a clogged main gas line, I recommend a complete disassembly of your propane heater.

Before you do that, turn the heater off and disconnect the gas tank. Disassemble all the gas lines. Then, use a wire brush and rubbing alcohol to clean the inside of the gas lines. Reassemble everything and try running your heater.

What to do if your propane heater still does not work?

You tried all of the fixes and your propane heater still doesn’t work? Then, I recommend you get a new heater.

You really tried everything to fix it.

My recommended propane heater is the Mr. Heater Buddy (click here to view it on amazon). You can also get its larger variant, the Mr. Heater Big Buddy.

I’ve written a review about both of them, including how long they last on a propane tank.

Check it out here: My favorite Propane Heater

Alternatively, if you are looking for a permanent propane heater (not a portable one), then I recommend you have a look at this article: Best Ventless Propane Heaters

My favorite heater on this list is a wall-mounted propane heater!


You can fix almost all propane heater problems by cleaning clogged components with rubbing alcohol.

The key is just to find out which component is clogged. Usually, it’s the pilot light’s gas line.

If this isn’t it, clean the thermocouple and the main gas line.

You can also replace the thermocouple with a new one.

Make sure that the gas hose connecting the propane heater with the propane tank has no kinks!

And, of course, you should make sure that you trigger none of the safety mechanisms (overheat protection, tip-over protection).