I have a keeprite high efficiency furnace that Was a part of my new house. It's 2016.
The Honeywell thermostat is set at 23 deg C. This is what happens when the temperature is below the cut-off
- I hear the furnace kicking in. No fan is heard
- The section right above the furnace become hot and suddenly the furnace shuts down. A burning smell is there from the vents in some rooms
- 4 times LED blinking is seen and after sometime turns to 7 times.
- I turn off the furnace and wait for 2-3 mins and start it again and everything is fine - blower kicks in after burner is ignited
I had the HVAC technician visit my place but I could not reproduce the issue.
Stuff I have already checked: combustion air flow from the vent is good. All wires and trips are great.
The fault codes are here: http://tradesmandrcool.com/wp-content/uploads/2016/11/KEEPRITEHighEff.pdf
Edit: I read somewhere that fan set to Auto is for cooling only. Tried to keep the fan ON and ran into the same issue again. However, at night the 7 flashes showed up against me I left the furnace running with fan set to ON. In the morning I observed the fan was running. By the way, there aren't any nests or dust. I checked for that as well