My Lennox Furnace Vents Freeze Up When It Is Very Cold

Freezing Vent Problems

• If you leave your vent frozen and simply wait for heat to melt the snow or ice that is blocking it, your furnace performance will suffer. The burners will not get enough air to properly ignite, which means they will not produce enough heat for the furnace to work efficiently. The flames that they do produce will be lower and may create contaminant problems in your furnace system.

Clearing Up the Problem

• The easiest way to remove ice or snow from your supply vent is to simply brush it away. Your supply vent typically exits out of a garage wall or through a foundation from the basement, usually close to the ground. If the vent is blocked with ice it will take longer to chip it away, but the process is still simple and highly effective. Resist the temptation to use a snow blower near your vent, since the vent can get caught and torn apart in the blower.

Hoods

• In order to prevent future problems with snow and ice, you can buy a hood for your supply vent. Hoods protect the opening of the vent from falling snow and building ice, making them safer in winter conditions. If you already have a hood, consider replacing it with a larger version. If you experience frequent, deep snows that completely cover the vent, hood or no hood, it may be time for a more drastic relocation project.

Relocation

• If you want to invest in the remodeling necessary, you can move your vent up the wall or even go through the roof instead of the wall. This can help solve your supply vent problems permanently and is even a standard method if you have a Lennox furnace in your attic. However, supply vents that come out on rooftops can still be covered in snow, so choose an angle where snow will not be able to reach the opening of the vent.