How Do You Replace a Gas Fireplace Thermocouple?

To replace a gas fireplace thermocouple, shut off the gas and electricity, remove the access panel, disconnect the pilot gas tube and then remove and replace the thermocouple. To find a replacement thermocouple, consult the owner's manual, take measurements of the existing part, or take the part into a hardware store to find a replacement.

The thermocouple is essentially a safety mechanism that allows the gas valve to remain open while the pilot light is safely lit. However, in the event that the pilot light goes out, the thermocouple loses its electric charge, which causes the connected magnet to close the gas valve. Some common symptoms of a faulty thermocouple or thermopile are pilot light failure and burner issues. To replace the unit:

  1. Turn off the gas and power
  2. Before accessing the thermocouple, turn off the gas and power to the fireplace.

  3. Remove the access panel
  4. Remove the access panel to the pilot assembly housing. The thermocouple is connected to the main gas valve. Remove any screws to pull the pilot assembly out to access the thermocouple. Most models are either screwed onto a bracket or snapped into place.

  5. Find a replacement
  6. Find a compatible replacement for the fireplace's model. Review the owner's manual for specific model numbers.

  7. Reassemble the unit
  8. Install the new thermocouple as the old one was positioned and reassemble the pilot light.