My Carrier WeatherMaker 9200 stopped heating with a code 31. From reading the forum and manuals it looks like it could be one of several things.
- Blocked drainage
- Blocked air duct
- Pressure Switch Failure
- Inducer Motor
The motor spins when the system attempts to fire up. I never see a glow in the burner view port. I have been unable to locate the inlet from the manual which shows where to pour antifreeze went winterizing. I read that you could pour water through to see if the drain is clogged.
When this first happened, it was off for a day, then came back on by itself. For that reason, I was led to believe it was the drainage. Perhaps the Pressure Switch is getting flaky. Is there a way to test the switch? Or should I simply replace it and work from there?