Wall Mounted Gas Heater Problems

Gas wall heater

Wall-mounted gas heaters are great ways to keep your home warm and cozy while keeping the electric bill low and keeping maintenance to a minimum.

However, maintenance is still key to having a top-notch, optimal-performing gas heater. If your heater is not working to its full potential, some issues may be easy to look for and simple to fix, others may need a professional to diagnose and replacement parts needed.

If in doubt, always contact a trained professional before attempting a fix yourself.

Gas Wall Heater Troubleshooting

This article is a quick guide to helping wall-mounted gas heater owners troubleshoot common problems and quickly fix them themselves. 

We have created a list of the top problems people seem to have with their home gas wall heaters and found ways the experts suggest using them to solve them. 

How Does a Gas Wall Heater Work and How to Fix it?

Gas wall heaters work very similar to radiators, where a pilot light is lit up from under the heating, coils that then push free-flowing heat up through the walls and all around the homes. In order for a wall heater to work, the gas supply must be continuously flowing into the pilot light, contently creating a source of heat.

Although this is a great way to heat your home, it can be a little difficult to troubleshoot a problem when one arises. 

Why Does My Gas Wall Heater Keep Shutting Off?

If your gas wall heater keeps shutting off, don’t get frustrated. There are many simple solutions to try before it becomes a serious or expensive situation. 

Faulty Thermocouple

A thermocouple is a tiny safety device that controls the flow of gas released to your pilot light on your gas heating system. This thermocouple is used to signal the gas valve that the pilot light is out and the gas tube needs to be sealed off.

If the thermocouple is faulty or damaged, it may have stopped sending signals, and the pilot light is unable to stay lite, causing your wall heater to stop working. 

To fix a faulty thermocouple, you can first attempt to clean the old one, and you can do this by wiping away dirt and debris or sanding off corroded metal. If that doesn’t work, unscrew one end of the thermocouple from the gas valve, remove the other end from the pilot light bracket, and replace a new thermocouple onto each end. 

The Pilot Light Flickers or is Weak

If your pilot light is flickering or too weak, it may not be able to keep your gas heater running correctly. The cause of a weak, flickering pilot light can be due to too much or too little oxygen. Sometimes pilot lights can be affected by drafts or a breeze flowing through the basement or room the system is set up in.

Other times, there may not be enough oxygen in the area, causing the flame to suffocate and keeping it from staying lite. 

In this situation, the only way to correct the problem is by controlling the air circulation in the area.

Blockages in the Pilot Tube

If there is a blockage in the pilot tube or the pilot tube is dirty, this will affect the performance of the pilot light causing it to turn off at random times. The pilot tube is a tiny thin tube that keeps fuel pushing through to the pilot flame, keeping the flame burning. 

If the tube is blocked, clearing it out is pretty simple. You can do this using a needle and pushing it into the line. The tube is super small, making a needle the only object thin enough to fit inside. 

Gas Wall Heater Won’t Turn On

If your trouble isn’t with the pilot lite, the problem could have something to do with the Thermostat, gas valve, or even the transformer. Here are a few options to look into if your gas wall heater.

Bad Thermostat

A thermostat is a communication between the room temperature and the gas valve. If your thermostat is not working correctly and communicates to the valve that the room air is warm enough, the gas will not turn on. 

If you think there is something wrong with your thermostat, you may want to check the batteries; if they are okay, try re-setting it through the factory reset option.

If neither of those work, you may need to replace the thermostat completely.

Gas Valve Issue

If the gas valve isn’t working correctly or locks up, then the wall heater could shut down, and the appliance won’t turn on. The gas valve is the part of the wall heater that causes the pilot light to ignite.

You should never attempt to repair a gas valve by yourself. The only one that should handle this type of situation are professionals with experience and the appropriate tools.

Gas Wall Heater Won’t Turn Off

One of the worst and most concerning situations you could run into with a gas wall heater is when it won’t shut off, and the heater is constantly running. If this is the case, there are a couple of things you should consider. 

Faulty Thermostat

Just like a bad thermostat will keep a gas wall heater from turning on, it can also keep them from shutting off. Although, this is a pretty uncommon problem these days, with all the safety features in place. 

Poor Room Insulation

This is one fix that doesn’t require shutting off the gas and any power to the wall heater. If you are trying to keep a room warm, but the hot air keeps leaking through the walls or windows and doors, your issue is due to the insulation, not the wall heater.

Gas Wall Heater Turns on But the House Doesn’t Heat Up

If the heater turns on but the doesn’t heat up, it probably has something to do with the heating element wiring. If the wiring is bad or loose, it will not send the correct signals and will not heat up. Fixing the wiring should solve the problem.

How Do You Reset a Gas Wall Heater?

There are times where all you need to do is re-set your gas wall heater if it isn’t working as it should. To reset a gas wall heater, you will need to go through a few different steps to keep yourself and the home safe.

First, make sure the pilot is out, then turn the temperature all the way down on the thermostat. Next, turn the circuit breaker off that provides power to the wall heater and cut off the main gas supply going to the furnace, leaving the line to the pilot lite still active.

Finally, you need to relight the pilot light, turn the circuit breaker back on, and open the main gas supply to the furnace. Once it is up and running, press the reset button and hold it in for a few moments, and then turn up the heat on the thermostat. 

How long do gas wall heaters last?

Depending on the wall heater’s make, model, and maintenance, these devices will usually last between eight and fifteen years. Many wall heaters can last well past that if properly taken care of.


Replacing your entire furnace and wall heater system can get very expensive and will be a long and rough process. Having the ability to troubleshoot and fix any issues on your own can be a life-saver. 

Remember, never do any type of work with gas lines and pilot lights unless you are taking safety measures and fully understand what you are doing.

If you do happen to have to replace your gas wall heater and want to change to electric, read our guide on the best electric wall heaters.