[casperitus493]

Good afternoon. I have an Amana Air Command 90, model GUC090X35A, P1173604F. The current symptom is the system will run on Heat constantly, but the burner won't ignite. We had this issue last winter and had a technician out to fix it - there was actually a blinking light then - and he sucked on a tube off of the pressure switch and it was fixed. We didn't seem to have the issue again until this past week, when I had to flip over from AC back to the Heat.

I have tried to follow the guidance of some of the forums that I found (e.g., suck gently on the tube, crank the heat way up), with no luck.

I was looking for a replacement pressure switch, thinking that I could just replace it and correct the issue, but, after talking to a parts specialist online here, found that the part is discontinued.

I just put new batteries in the thermostat, reset and reprogrammed it, and it still doesn't fix the issue.

Before I call a technician back out, does anyone have advice as to how to self diagnose the issue?