Running Your AC in Winter

Most Utah homes have central air conditioners. While summer is the most common time to run the AC, some homeowners wonder—can you run the AC in winter? After all, cooking can overheat the kitchen, and the bedrooms can get stuffy, even when it’s quite cool outside. But does running the air conditioner in cold weather damage it?

The short answer is that you should avoid running your air conditioner when it’s below 50 or 60 degrees outside. Here’s a look at why this can be problematic and what you can do instead.

What Happens to an AC Unit When You Run it in Cold Weather

Refrigerant is the key to air conditioning. Today’s AC units run on R-22 (Freon, which has been phased out for environmental purposes) and R-410A (Puron, a cleaner alternative). Both refrigerants thicken when the outdoor temperature drops, preventing them from flowing as easily. Running the AC in cold weather also makes the refrigerant more likely to fall below its freezing point, leading to ice buildup on the outdoor condenser and indoor evaporator coil.

If you need to run your air conditioner for a few minutes—whether to test it for issues, show a prospective homebuyer that the unit works, or another reason—you should wait until the temperature is above 50 degrees for a few days. This allows the refrigerant to warm up and ensures no ice buildup.

How to Circulate the Air in Your Home without AC

Your HVAC system may not run much when the outdoor temperature is around 50 to 60 degrees, leaving your home feeling stuffy and hot. Here are some ideas to combat this:

• Crack a window to invite fresh, cool air inside.
• Turn on a ceiling fan.
• Set your thermostat to fan-only mode. This runs the blower to circulate air through the ductwork without turning on the heating or cooling components.

What About Heat Pumps?

Some HVAC systems can heat and cool a building by moving heat from one place to another. These units are called heat pumps. They look and function like air conditioners in the summer, but a reversing valve allows them to extract heat from cold outdoor air and deposit it into your home.

Heat pumps are intended to operate in the winter, so it’s perfectly safe to run them no matter how cold it gets outside. If you’re not sure whether your air conditioner is actually a heat pump, look up the brand and model number online to find out.

You’ll turn your full attention to your air conditioner once the weather warms up outside. Make sure it’s ready for another Utah summer by scheduling AC maintenance with Parley’s PPM Plumbing, Heating & Cooling. We have over 40 years of experience providing unparalleled customer service and quality HVAC maintenance.

Ready to schedule an appointment? Please call 801-877-2184 if you’re a Utah County resident or 801-877-2536 if you live in Salt Lake County. You can also contact us online with any questions you have.