I tried both cleaning my furnace's flame sensor and later installing a new flame sensor. However, the furnace still shuts off after only a few seconds of the burners operating. Do you have any ideas on what the source of the problem could be?


I'm really not sure based on this information as there are a lot of possibilities and some electrical testing would need to be done to narrow it down. Limit switch and pressure switch and circuit board would be my suspects.

Updated on January 8, 2018

Original Article:

How to Clean A Furnace Flame Sensor
By Dan Robbins