The Spark Electrode sense the flame and also sends the spark. IF the spark sparks and lights, then the Piezo tower on the board(where the spark electrode wire spade connects to) is defective OR (most likely) the solders for that Piezo Tower have ben broken loose. The most common thing to do this is NOT using a back up tool when removing the the Spark plug wire from the Piezo tower on the control board. What you do is remove the Control board and where the Piezo tower is soldered on the back side of the board, you re-solder those points. IF that does NOT fix it, I would replace the Spark Electrode. It takes minimal flow to SPARK the ignition. but requires perfect return to the board from the electrode to sense the flame. I would replace the Spark Electrode/wire FIRST, then do the solder if needed. IF the Spark Electrode and the solder of the Piezo tower fails to fix, then you have to replace the board. If there is a hairline crack in the White ceramic of the spark plug, the return flame sense signal will not make it. Doug
