I just replaced the thermocouple in my gas heater as the pilot wouldn't stay on after lighting. The old thermocouple had developed a hole in the tip and the tip was discolored when I removed it.

I checked the pilot today and it went off sometime today or yesterday. I noticed that the new thermocouple developed a hole in the tip and the tip was also somewhat discolored.

I relighted the pilot and it appears to still work fine.

Is the thermocouple suppose to develop a hole in the tip after being exposed to the pilot flame for a few days?

Edit: I have removed the thermocouple and it is not a hole, but just discoloring. I have cleaned the tip and reinstalled it.

Picture: thermocouple

  • What make/model is the heater? What make/model is the replacement thermocouple? Can you post photos of the damage? Dec 9 '16 at 12:43

The Thermoucouple should withstand the heat of the pilot without damage. If it is still working you are ok but I would get a backup in case it fails. Thermocouples work with 2 dissimilar metals fused together and they create a small voltage when heated. If the junction of the 2 metals is damaged then the Thermocouple will not work. Some manufacturers call there Thermocouples Thermopiles I have used universal replacements and never had a problem as long as they screw in correctly.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.