How To Inspect And Replace The Thermocouple On Your Gas Furnace

If the pilot light on your gas furnace keeps going out, the thermocouple may be to blame. This device is hooked directly to the pilot light and can sense when the pilot light is lit, signaling the gas valve to open. You can inspect and replace this part with a few, simple steps. After adjustments are made to the current one or a new one has been installed, your furnace will operate as it usually does. 

Use These Items

  • emery cloth
  • wrench
  • testing kit
  • replacement thermocouple
  • screwdriver

Inspect The Thermocouple

Before removing the thermocouple, you can make some adjustments to see if they will correct the problem. Turn the gas off at your home before beginning so that you do not accidentally become injured. Open the access panel that houses the pilot light and thermocouple. The thermocouple is the long tube that has a couple clips holding it into place. Make sure that the nuts that are connected to the thermocouple are tight and adjust them if needed.

If the end of the thermocouple is white, it is a sign of carbon build up. This can prevent it from heating up. Sand this substance off with an emery cloth. Once finished, turn the gas back on and light and ignite the pilot light. If your furnace stays on, the problem is fixed. If not, you may need to purchase a replacement thermocouple. 

Remove And Replace The Thermocouple

Turn off the gas, once again. Loosen the three nuts that are holding the thermocouple in place. Gently pull out the clips. Unscrew the bracket that is around the thermocouple. After doing so, the part will be able to slide out easily. Bring it with you to a hardware store. Have it tested to ensure that it is the problem that is preventing your pilot light from staying lit. The hardware store should have a testing kit on hand to do this.

Because you have the thermocouple with you, you will be able to receive the proper part if you need to purchase a new one. Reattach the bracket and slide the new thermocouple inside. Attach the clips to the gas supply tube. Tighten the bolts. Turn on the gas and ignite the pilot light. Your furnace should work properly. In the future, be sure to inspect the thermocouple on occasion. By doing so, you can remove any build up and lengthen the amount of time that it works. Contact a company like Colorado Comfort Systems for more information.