What Should I Do if My HVAC Freezes in Winter?

When the temperature outdoors drops below 32 degrees Fahrenheit, your high-efficiency furnace or heat pump can freeze. 

That may seem odd because most furnaces sit indoors, and at least a portion of your heat pump (the evaporator coil and fan) is indoors. 

But consider that high-efficiency furnaces and heat pumps produce condensation as they operate. That moisture has the potential to freeze.  

Carrier Cooling Center can help you prepare for that possibility before winter. We make it convenient for you to connect with a Carrier Factory Authorized Dealer in Arizona, parts of California, Idaho, Nevada, and El Paso, Texas through our online directory.

Heat Pumps and Freezing

Heat pumps and furnaces operate differently, although both create condensation that can freeze under the right conditions.  

A heat pump transfers heat from the outdoor air in the winter and moves it indoors via refrigerant. As the refrigerant extracts heat from the air, it creates condensation that can freeze on the condenser coil in low temperatures. 

Heat pumps have a defrost cycle that can melt thin layers of frost and ice off the outdoor coil. However, it may be no match for a thick accumulation. Ice storms, snowstorms, and leaky gutters can coat the outdoor components in ice.

Low refrigerant, a faulty defroster, and poor airflow are other factors that can contribute to your heat pump freezing. Check your outdoor unit frequently in cold winter temperatures, and remove snow and other debris that might restrict airflow.  

Maintenance is the best solution to avoid freezing the heat pump in your home this winter. A professional tune-up can identify potential problems, such as refrigerant leaks and defroster problems that lead to freezing in cold temperatures. 

At Carrier Cooling Center, we make scheduling spring and fall heat pump maintenance easy. Check our directory of Carrier dealers to find a pro near you. 

Furnaces and Freezing

A high-efficiency gas furnace creates heat by burning fuel rather than transferring it. These units use gas-fueled burners and a heat exchanger to heat air pulled from the outdoors.

The conditioned air is blown through ductwork to heat your home, while toxic exhaust gases created by combustion move into a second heat exchanger. 

The heat exchanger extracts usable heat from the exhaust gas, which cools and condenses before exiting your home. The moisture it leaves behind drains through a condensate line, typically a PVC pipe, to the outdoors or an indoor drain.

Condensate that does not drain properly can freeze in the drainage pipe. That can cause drainage back-ups that will shut your furnace down. 

Be sure snow and other debris are not blocking the drainage pipe opening.  If ice accumulates at the outlet, you can try to break it up by using an ice pick or screwdriver. Try using a hot water bottle to thaw out the frozen condensate line. You also can insulate the outdoor pipe to help prevent freezing. 

Some pipes that are too long or placed at an incorrect angle may be prone to icing.  A Carrier dealer can recommend a more permanent solution than hot water bottles and insulation if your condensate pipe frequently freezes. 

Call the Experts Today

Need help with your HVAC system? Find a Carrier dealer in Arizona, parts of California, Idaho, Nevada, and El Paso, TX, through our Carrier Cooling Center directoryClick here to get started.