Replacing And Maintaining The Thermocouple In Your Gas Furnace

Posted on: 29 January 2015

If the pilot light to your gas furnace isn't staying lit, you probably need to purchase a new thermocouple. A thermocouple is a special sensor that is connected to the pilot light. It is responsible for measuring voltage and without it, your furnace won't work properly. You can easily replace this part by following a few steps.

Use These Tools

  • pliers
  • adjustable wrench
  • sandpaper
  • sanding block
  • replacement thermocouple
  • lint-free cloth
  • vacuum cleaner

Remove The Thermocouple

Turn off the power to your furnace. Open the access door to your gas furnace. Locate the pilot light. Right next to it, you will see a long, thin rod with two clips connected to it. This is the thermocouple. Remove the clips from the pilot light by gently pulling them off. Loosen the nuts that are connected to the thermocouple with a pair of pliers or an adjustable wrench. Once you remove them, slide the thermocouple through the bracket that is holding it in place. 

Insert The Replacement

Bring your old thermocouple to a hardware store to purchase a new one. Once you get back home, insert the new one into the bracket and replace the nuts. Attach the clips to the pilot light. Wipe off the interior of the furnace with a lint-free cloth to remove any dust that is present. If the inside is extremely dirty, use a vacuum hose to collect the dirt. Having a clean furnace will help it work more efficiently. Relight the pilot light before closing the access door. Turn on your furnace to make sure that it is working properly. 

Maintain Your Furnace

Keep the thermocouple clean and the inside of your furnace maintained so that you do not encounter any additional problems. Use a sanding block to remove any buildup from the end of the thermocouple if it ever becomes apparent. The substance that you may see will be white. It is carbon and it can cause the thermocouple to malfunction if it isn't removed. Wiping the inside of the furnace off with a cloth on occasion is also important. Checking the status of your furnace every couple months will be sufficient.

Have your furnace inspected by a heating specialist each year. If you schedule an appointment to have your furnace inspected before it gets cold outside, any small problems can be repaired so that your furnace will be ready for use when you would like to heat up your home. Click here to read more.