I have a York Gas Furnace, Model P4CSD12N08001A that has symptoms of Flame Detection Failure. I have dismantled the burner system to remove the pilot light assembly. I cannot find a Flame Detector unless it is built into the Ignitor. The assembly contains the Pilot Flame opening and a spark igniter but there is not a visible Flame Detector. Can you tell me if the Igniter also serves as Flame Detector on this model?
(Honeywell) system the spark rod is the flame rod. Pull the pilot and clean the pilot and using some soft clean emory cloth clean the rod. Reinstall the pilot and if you know how to take a microamp reading check the microamps they should be between 2 to 10 microamps, normal is around 3 to 5.
If you are not a professional you may need to contact one for this unit. It is also a good idea to have them do a combustion test at the same time.