I posted a questions months ago, that it randomly decides to not start. Random as in work for a few hours, a few days, a few weeks….whenever it feels like not working, random. I went and replaced the control board, the inducer motor, the inducer control, the pressure switch, the igniter, the pilot assembly, the gas valve and the 24v transformer. I still have issues. I checked and cleaned the intake and exhaust vents, the air tubing, the collector box, the condensate drain, everything is clean or new. I hear the gas valve open and closing, the pilot open and close, even the pressure switch open and close. The system seems to operate as it shoud, but just sometimes it fails after 15 seconds to ignite, never get to ignition spark.
Whats next? 25yo Carrier 58dxa gas
Best Answer
I have found there is nothing more important than a good ground on units doing this and I mean "A GOOD GROUND". Run a second one if necessary to your burner manifold and ground it to the frame somewhere that will give you a positive ground.
Then do the same with your control board. Make sure the transformer is feeding the control system correctly too. Not trying to doubt you, but sometimes people wire the output and common wrong. I have seen it. If the igniter is still erratic, sometimes the diaphragm in the draft switch doesn't make the switch because of trash floating around in the thing and the nipple getting partially plugged. These are just things I have found on jobs.