What to Do When Your HVAC System Freezes in Winter: The Defrost Cycle

snow and ice hanging off a frozen house roof

We have some pretty brutal winters here in South Dakota, with most extreme temperatures happening around December and February. While ice fishing and snow tubing are fun ways to get through the winter, it’s always nice to end the day nice and warm in a heated home. But what happens when snow and ice cause your HVAC system to freeze in the middle of winter? It’s important to know what steps to take so you can get heat back in your home as quickly as possible.

Heat Pump Frozen? Here’s What You Need to Know 

When it’s cold outside, heat pumps work just like an air conditioner, but in reverse. The refrigerant takes heat from the outside air (yes, even in winter!) and uses it to make heat for your home. However, sometimes during the transfer, excess moisture causes the coils to freeze up, which prevents your system from working like it should. 

It’s actually pretty normal for your heat pump to freeze up, at least temporarily. In fact, your heat pump has probably been frozen before, but thanks to the defrost cycle, you didn’t notice. Most heat pumps have a defrost cycle, and it goes off automatically, running at timed intervals to help keep the system from freezing over. This way, you never have to be without heat. 

If your system doesn’t do this by itself, you should be able to turn it on manually. However, not all systems have a manual defrost cycle option; as long as you know the model of your system, you should be able to find out with a quick search online.

And finally, if your heat pump freezes for more than a few hours and doesn’t seem to defrost at all, then you may be dealing with a bigger issue. Your best bet here is calling in a professional so you can get things taken care of ASAP, before costly damage occurs. 

Some Helpful Tips

Sometimes, you can’t stop your heat pump from freezing up. There are a few things you can do to help prevent it, including:

  • Keeping your unit clear of debris and dirt
  • Staying on top of routine maintenance
  • Changing the air filter regularly 
  • Putting a cover over your unit

Preventative maintenance like this is often ignored, but it’s really so important. If you stay on top of it, you should have little issue with your system, and therefore won’t have to deal with a frozen heat pump or expensive repairs or replacements for your system. 

Keep Your HVAC System Working All Winter Long

At Larry’s Heating & Cooling, we know how important it is to keep your home comfortable and warm when the cold weather arrives. Our best recommendation is to get your system checked out before the ice and snow hit; this way, you can have peace of mind knowing you won’t have to worry about your heat going out in the middle of winter. 
Need a pro to come out and take a look at your HVAC system? Contact our heating company in Yankton, SD today! We proudly provide 24/7 heating and cooling services to families in Yankton, Vermillion, and other nearby SD communities, all year long.

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