After living in the same house for 7 years and having much more snow, my vent on the roof was full of frost. The thermostat would kick on,but no heat.
This is the second time in 2 mths I had the vent taken off and cleared of frost. Once the vent was cleared the problem was gone. An elbow was left instead of 2 elbows on a pipe that was previously attached.
I asked the tech what else it could be, and he said maybe a secondary burner.$5000 for a new furnace installed and vented through the side if the house and not the roof. Will wait
Vent removed from on roof [