I think i know why this is happening i m just curious how to remedy it.
Furnace roof vent ice.
This structure generally uses the furnace vent pipe through roofbecause the b venting pipe is designed in vertical manner.
In contrast modern high efficiency condensing furnaces exhaust much cooler gasses and need only plastic pipe materials such as pvc cpvc or abs for their exhaust vents some high efficiency furnaces also include a plastic pipe for intake area and all types.
The unit will reset.
When such obstructions interfere with the operation of the furnace they starve it for air but be assured there.
As the temperatures are dropping your furnace is working even harder.
My heater keeps shutting itself off to prevent overheating because its roof vent is blocked by ice.
Though large restrictions in an intake or exhaust vent often results in the furnace shutting down in a safety lockout mode smaller restrictions can also cause ice to form around the vents.
Goose neck vent the master flow 4 in.
Run the vent pipe up through the roof and install a metal or pvc flashing collar over it.
When the vent is withdrawing air from the house it expels the gas outside through the vent.
Match the vent pipe to the furnace maker s recommendations either sheet metal or vinyl.
This vent is designed to be used on 4 in.
Goose neck vent in black can be used to cover exhaust pipes extending through your roof or for attic ventilation.
The master flow 4 in.
I don t know for sure but you are probably pushing the limits of this particular furnace and exhaust setup.
Also known as the type b this vent is operating on the natural air convection.
Something you may have noticed is snow and ice building up around the vents of your high efficiency furnace.
The solution is simple.
Objects sticking out of a vent can allow snow to accumulate and ice over as snow is repeatedly thawed and frozen again.
The gases in your furnace are condensing and it appears to be so cold that they freeze almost immediately after touching the cold air.
We have a new high efficiency furnace and are anxious when snow on the roof or ice buildup from condensation blocks the vent.
What you are seeing in picture 1 below is the aluminum sleeve and cap i installed when replacing my roof.
Is this the smart thing to do.
To find where the intake or exhaust pipe and vent are located go to the furnace and look for a black or white pipe not the metal heating ducts going from the furnace to an outside wall.
We often don t use the furnace until the area is cleared.
Turn the furnace off wait a minute and then turn back on.
Clear the snow from the intake and exhaust pipe.
It s made of zinc coated galvanized steel for durability and reliability.