Can Cold Weather Make Central Heat Freeze?

Heat Pump Evaporator

• Some central heating systems use a heat pump that draws in heat from the air outdoors and passes it inside. If conditions are warm enough for the heat pump to still operate but too cold for the evaporator, the outside portion of the heat pump can draw moisture and freeze it on the evaporator coils. This causes the heat pump to lose efficiency and eventually fail.

Other Furnace Options

• If you have a gas furnace, freezing may still be an issue. Modern gas furnaces tend to use a reclamation system that draws heat from its exhaust. Unfortunately, it also draws moisture, and this created condensation can freeze in cold temperatures. This can lead to blocked drains or condensation lines, corrosion and cracks in your furnace.

Ductwork Issues

• Your ductwork is also susceptible to cold weather. Ducts cannot freeze themselves, but as their metal contracts in the freezing conditions, they can start to develop gaps and leaks. This lets the freezing air into the ducts, directly countering the warmth that the central heating system is producing. The result is an inefficient heating system that wastes time and money.

Pipes

• Your central heating system uses pipes for its drain lines (to get rid of condensation), and potentially for water lines if you have a heat pump system that uses water instead of refrigerant to carry heat. Pipes filled with water are always in danger in cold weather. If the water inside freezes, the pipes can crack, creating multiple leaks and leading to damage of surrounding materials.