• Please note, some of the links on our site are affiliate links (Learn More)

5 amber/yellow flashes on York furnace YP9C080C16MP12CB


Premium Member
Sep 3, 2005
Ontario, Canada
Model Number
1-5 years
I have a York YP9C080C16MP12CB furnace. I was doing some work near the furnace and I noticed it was flashing yellow/amber 5 times. I checked the sheet attached to furnace door and for the 5 amber flashes it says: "High altitude OR vent, intake OR termination problem". Some sites I visited online say something like "vent and/or combustion air system is restricted" when discussing the 5 amber flashes.

There are two problems, for me, I hope someone can help me with. The first is what does these words mean? What is the issue causing the code? The second is how do I narrow all of this down to a fix? To further complicate things, the furnace seems to be working correctly. Thanks

UPDATE: Just went to the furnace to see what was happening and when I raised the thermostat to call for heat I was getting two flashing yellows only which says it is normal. Any ideas?
Last edited:
If you feel that you have benefited from this site, and would like to show your appreciation.