The heat went out while my wife was in our new home we had built in Norther Wisconsin. The Heating contractor did not answer his phone or call back. Someone else came to check out the system to get it relight and after many attempts, found that the flue where exhaust gases vent to the outside was right next to the air intake of the furnace and that had iced up because of the intake of the moist exhaust from the flue.
What should we do?
I’m assuming that you have a high efficiency furnace installed – if the pipes have frozen, you have to remove the ice blocking the inlet / outlet. The reason for ice buildup is usually improper installation of the PVC pipes:
1. exhaust must be sloped at least 1/4″ per foot towards the furnace
2. positioning / spacing of the exhaust and intake on the exterior wall is also very important. The safest way to determine if your furnace’s PVC vent pipe has been properly installed is to search appliance manufacturer’s website for a installation manual. It should describe vent positioning and all clearances in detail.