You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

Why Is My Air Conditioner Frozen in Summer?




Many homeowners have experienced the frustrating and costly issue of a frozen air conditioner. While it may seem like a daunting problem, there are actually quite a few potential causes of an AC unit freezing up.

In this article, we’ll explore some of the most common reasons why your air conditioner might freeze and what you can do to fix the problem.

Telltale Signs of a Frozen AC

Not necessarily. A good way to tell if your air conditioner is frozen is to check the refrigerant line. If it’s covered in ice, that’s a frozen system! You will see crazy photos online where someone’s entire unit is frozen, but that’s pretty rare. Other signs of a frozen AC include condensation in the drain pan or on the indoor unit, or… well… the AC not working is a pretty good sign that this could be the issue!

Commone Reasons ACs Freeze

One of the most common reasons for an AC to freeze is simply because your filter is dirty or clogged.

How the heck are these two things connected? Well, a dirty or clogged filter will restrict airflow to your unit. The way your air conditioner is supposed to work is that the warm air from indoors gets taken into the return vent, through the filter, and over the evaporator coils, which removes the heat from the air. The refrigerant is what absorbs this heat, causing the refrigerant to turn from a liquid to a gas.

However, suppose your dirty air filter makes it impossible for air to flow through. In that case, not much air is blowing over the evaporator coils, and the refrigerant can’t turn into gas like it’s supposed to… instead, it freezes!

Another thing that could be impacting airflow is a leak in your return vents. These are the vents that allow air to be sucked into your unit in the first place. If these are leaky, again, not enough air is moving, and you guessed it… the AC freezes.

Quick, Simple Fix for Your AC

A frozen AC is almost always an airflow problem, whether the culprit is a clogged filter or another reason.

The good news is that this problem is relatively easy to fix! First, change that dirty air filter! Then, power off your AC at the thermostat and switch the fan to “on.” That way, the air conditioner is blowing warm air, quickly allowing the system to thaw, heating the evaporator coil and the refrigerant.

Give this process a day, then turn your regular AC settings back on.


If thawing the system manually doesn’t seem to be doing the trick, it’s time to call in a professional. We can look at your unit and figure out if something more serious is going on, like a leak in your return vents.

A frozen AC is never fun, but we hope this article has given you some clarity on what might be the problem! You don’t want a frozen AC, especially in summer! 

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