How To Replace Thermocouple On Gas Heater? 8 Easy Steps!

How to replace thermocouple on gas heater? To understand this question, you first need to understand what a thermocouple is. So, what is a thermocouple? A thermocouple is a device usually present inside a gas heater, analyzing the pilot light and preventing any accumulation or explosion of extra or unused gas. It helps keep you safe from the risks caused by the explosion of a gas heater. 

The gas heater is an essential item at home, especially when it’s cold outside. It keeps you warm and comfy by using natural gas as a heat source. Most gas heaters come with a thermocouple that protects them from any bad incident.

How to replace thermocouple on gas heater

But, a thermocouple can be worn or gets old after some time a needs to replace. Replacing a thermocouple is a daunting task, but with the right steps, you can easily change it. We have a step-by-step guide that will help you to change thermocouples on gas heater easily. So, without further ado, let’s get started!


Steps To Replace Thermocouple On Gas Heater

If your thermocouple has stopped working, there is an urgent need to replace it. If you use a gas heater without an active working thermocouple, you risk yourself. Follow the below discussed steps accurately to get a guide on how to replace thermocouple on gas heater.


Step #1. Turn off the gas heater

Before starting, make sure you have turned off the gas heater, disconnecting its connection with any external energy source. The power button can be on the side or top of the furnace, and you can quickly turn it off from there. 


Step #2. Turn off the gas connection

Disconnect the gas source connected to your gas heater by closing the gas valve. After turning off the valve, check if there is any gas present. If not, then proceed with your work. 


Step #3. Remove the upper cover

Use a screwdriver to loosen the nuts holding the upper panel in place. Once the panel is removed, keep it aside. Now look for the thermocouple; it consists of small tubing and wires with metal brackets. You can detect it near the pilot light. The other end of the thermocouple is connected to the gas valve. 


Step #4. Remove the thermocouple

For removing the thermocouple, you first need to de-screw the nuts that tightly connect the thermocouple with a gas controlling valve. After this, start loosening the screws that hold the brackets of the thermocouple and sensor in place, and remove the sensor from the brackets quickly. Now, you can remove the whole thermocouple from the gas heater.


Step #5. Installation of new thermocouple

Adjust the new thermocouple in a position that resembles the old thermocouple. Then, place it, insert the brackets and sensor like before, and reconnect the new thermocouple with the gas valve tightening the screws. 


Step# 6. Resupply the gas and power

After placing the new thermocouple correctly, turn on the gas valve and provide power to your gas heater to check if the thermocouple started working or not. 


Step #7. Ignite the pilot light again

Turn on the pilot set by the knob and push the ignite option. If there is no such option available, use a matchstick to turn it on. Wait for 20 seconds, and see if the flame in the pilot light rises. If yes, then release the knob and keep the pilot light burning. It may also be a good idea to read about how do i know if my pilot light is out.


Step #8. Place the upper cover back

Your thermocouple is replaced correctly, and the pilot is also burning well. You can place the upper cover of the gas heater again. Tighten the screw, fix it and enjoy a warm room in the cold weather.


Reasons Why Your Thermocouple Is Not Working

Several problems can cause trouble in the working of a gas heater, and a defective thermocouple is one of them. The different reasons that make a thermocouple defective are:

  • Broken: A broken thermocouple fails to detect the pilot flame, and the gas heater won’t work. However, a thermocouple can be easily replaced by following simple steps. You can also call a professional technician to help you with it if you are afraid of making things messed up. 
  • Dirt or debris: The dirt particles clog the thermocouple causing a failure to work. When the thermocouple is constantly exposed to flame or gas, it gets worn out over time, and a slight problem can result in its malfunctioning. But, this is not a big issue. You can easily remove the dirty thermocouple, clean it with a brush and place it again. After this, your thermocouple will start working like usual. 
  • Improper setting: For a thermocouple to work properly, it must be in close contact with the pilot light. The pilot light should engulf the thermocouple rod so that the thermocouple starts quickly working when the pilot light is on. If the thermocouple fails to detect it, there are high chances that your thermocouple is not properly set up.


It’s A Wrap!

Everyone needs a gas heater in cold weather as it’s an efficient and cheap way to keep your home warm. But when your thermocouple gas heater goes bad, it needs immediate replacement. This article will guide you on how to replace thermocouple on gas heater. Following the above-discussed steps, you can easily return it without professional help. You can also get information related to how do thermocouples work. Don’t hesitate to know these things too; read about how to clean thermocouple on patio heaters and how to change thermocouple on hot water heater.

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