How To Clean A Thermocouple On A Patio Heater: Easy Guide

If you’re new to using propane patio heaters after a long time in the winter months, you may find it difficult to know why your patio heater won’t stay lit. Once the thermocouple of your patio heater gets clogged with soothes, dirt or insect after you left it unused for a longer time, the next time you want to use it it won’t stay lit because you will need to unclog it first.

Spiders and bugs can accumulate in the gas tubes during the warm season when the heater is not in use. The debris blocks the gas from reaching the igniter and needs to be removed for a proper function.

So today we will be discussing in this article how to clean a thermocouple on a patio heater.

You can clean a thermocouple by turning off the fuel supply and removing the thermocouple from the pilot tube. Use a dry sponge or steel wool to clean, and use a pencil eraser if necessary to remove the hard-to-reach parts. Do not use any chemical cleaners.

And because patio heaters provide a comfortable environment during the cool fall and winter months by raising the nearby air temperature. You have to know how to maintain them.

What is A Patio Heater Thermocouple

How To Clean A Thermocouple On A Patio Heater
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Patio heater thermocouple is a piece of metallic tubing that’s smaller than soda straw, it activates the main control valve after the pilot light is lit. Every natural gas or propane patio heater includes a thermocouple it is the essential part of any patio heater.

So when not in use for a longer time, it gets clogged up. Therefore, you to carry out maintenance next time you want to lit your heater.

What Does A Thermocouple Do In A Patio Heater?

Thermocouples are small and fragile, they are a very important part of a heater system and if they are not cleaned properly they can damage your heater. Thermocouples are devices that measure the temperature of a fluid or gas. This device is used for measuring temperatures, they come in many different sizes and shapes.

Essentially, a patio heater thermocouple is a protective device on a propane shed heater. What it does is to maintain the furnace pilot lit by sending a small electric current to a sensor at the gas valve of the patio heater.

Tools Required For Cleaning Patio Heater Thermocouple

Before you start cleaning your patio heater, you’ll need to be prepared with the right equipment. You’ll need items that are needed to properly clean your patio heater, such as:

  • Cloth Sandpaper/Dry Sponge
  • Steel wool
  • Screwdriver
  • Pencil Eraser

How To Clean A Thermocouple On A Patio Heater

There are many ways you can have your patio heater thermocouple cleaned but below are the most convenient and easier ways to do it. Once you have all the tools follow this step by step guide to do the cleaning process:

  1. First step is to Shut off the heater fuel supply. 
  2. It’s time to disconnect the gas line from the heater.
  3. The next step is to find the thermocouple, which can be found in the owner’s manual. You can look over the user’s manual to get a clear understanding of the location of the device.
  4. Now you need to take the screwdriver and loosen the screws around the thermostat.
  5. After removing the screws holding down the battery, lift the thermocouple from the pilot assembly. It’s easy to pull and remove from the pilot assembly. Once all screws are removed, you can take out the thermocouple.
  6. Now you should take a sandpaper, dry sponge or steel wool.
  7. Using steel wool, you can gently rub the thermocouple. If you are using a dry sponge, you need to make sure that you are using the abrasive side of it. You will not be able to complete the cleaning process effectively if you are not using the abrasive side.
  8. You should continue to clean the thermocouple until you have removed all soot.
  9. The best way to clean the thermocouple is to use the pencil eraser to remove the dirt that is trapped in between the threads of the screws.
  10. Reconnect the thermocouple to your patio and test it for efficiency. It worked!

Once you have checked that, you can check the functionality of your patio heater and make sure it is working properly.

We have also compared electric patio heater and propane patio heater here to guide you on which is best for you depending on your needs.

Another Method

You lift the protective flame screen off the patio heater, unscrew the nut and pull out the thermocouple. With a water hose, rinse the inside of the thermocouple tube, let it air dry, then re-connect it.

Important Safety Notes For Cleaning The Thermocouple Of A Patio Heater

While doing any job it’s advisable to keep in mind some safety measures same applies when cleaning thermocouples. Let’s have a look at the safety notes:

  • You must keep the area free of any sources of flame, such as candles or matches, while you’re working on it.
  •   Wear goggles to protect your eyes from dust.
  • Use hand gloves to protect your hand from any accidental cuts.

Be careful with these safety tips, and use them as a reminder when working around gas or fire. Use flame-resistant gloves to prevent accidents, and remember that if you do have an accident, you could be harmed.

How Can You Know If Your Thermocouple Is Defective?

If you see the Pilot tubes can become kinked or bent. In this case, you have to replace the thermocouple.

In another case, you may need to install a new furnace. You may need to replace the thermocouple or even the entire pilot tube. Check out the following tips to help you decide what needs to be done. If your pilot tube becomes kinked, bent, or damaged, you will need to replace the pilot tube.

What happens If The Thermocouple Fails?

If you have a clear understanding of what happens to the functionality of your patio heater in the event of a failure of the thermocouple, it’s better to get it repaired sooner rather than later.

If after removing the thermocouple you found out that it’s much corroded that cleaning it is a waste of time and energy, then consider changing your patio heater thermocouple for efficient heat output.

If your outdoor patio heater’s pilot light could be damaged. If it is not cleaned regularly, you will have to go ahead with cleaning the thermocouple.

This will help in ensuring that you are getting the desired heat for your patio.

How To Bypass Thermocouple On A Outdoor Patio Heater

If you don’t want to replace it and want to use the heater then I’m going to show you how to bypass a thermocouple on an outdoor patio heater. This is a great way to troubleshoot if your heater isn’t working or if the thermocouple is bad. If you are having trouble with the performance of a heater, it’s worth trying this out. This is the part that connects the heater to the thermostat.

Here are some steps to do this:

  1. Bend the right tilt switch wire so that it touches the left tilt switch wire.
  2. Remove the thermocouple using the 8mm wrench.
  3. Use the 13mm socket wrench to pull the valve housing to one side.
  4. Now you can remove the valve using the pliers. It’s the component that moves the thermocouple in and out. It generates electricity for the electromagnet.
  5. Now your task is completed and you have successfully bypassed the thermocouple it’s time to Reattach it by using the 8mm wrench again.

I hope you enjoyed this guide on bypassing a thermocouple. Let me know in the comments if you have any questions. Also, please share this with others if you found this helpful. I’m always open to new ideas and feedback. So, let me know what you think in the comments below


The thermocouple of your patio heater needs to be cleaned at least once every year, and it may need to be cleaned more frequently if it’s been in use for a long period of time. If you’ve got your heating system serviced regularly, you should be able to do this yourself. There is no need for an expert to get the job done.

It is important that you regularly Clean A Thermocouple On A Patio Heater to make sure that it continues working without any problems.

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