[Joboy]

Furnace fires while under ignition but shuts off. Thermocouple or flame sensor? How would I clean the sensor? Thanks.

 

[HVAC1000]

You can best clean it with a scotch brite pad. I've heard of some techs that like to use dollar bills the clean them off too. Do not use sand paper or anything very abrasive. It will create large scratches that will make the sensor dirty much faster

 

[Joboy]

Thanks for the tip. Can I just reach in and clean it or do I have to take the sensor out of the burner tube?

 

[carmon]

take it out....