Is your AC struggling during these peak summer months? Utah’s temperatures have reached new record highs in 2026, and that’s left many homeowners with lagging systems right at the moment when they need reliable cooling most.
While there are several potential reasons for AC units to have trouble in 90+ degree weather, one common symptom can tell both homeowners and HVAC technicians a lot about the root cause and how to fix it. That symptom is a frozen AC system.
It might sound contradictory for a unit to freeze during the hottest time of the year, but that’s actually the time when it happens most. Freezing happens when heat doesn’t reach the evaporator coil, and that can be caused by poor ventilation, low refrigerant, or a more serious equipment failure. If you’re wondering how to tell if AC is frozen, what you can do about it on your own, and when to call a technician, this is the guide for you.
How to Tell if AC is Frozen
If you’ve experienced any of these issues recently, they might be signs of an AC frozen over:
- Poor airflow when it was fine a few days ago
- Your house not keeping the temperature you’ve set on the thermostat
- The AC blowing warm or room-temperature air
To check for ice in the system, you can either take a look at the compressor or the furnace, but in my experience, the furnace is usually your best bet. The evaporator coil sits on top of the furnace–peel back the rubber gasket, and if you see white underneath, that’s the most surefire sign of an AC unit frozen over.
How to Fix a Frozen AC: DIY Troubleshooting Steps
The first thing to always make sure to do once you’ve determined you have an air conditioner frozen inside is turn off the system. Keeping it running while frozen increases the likelihood of more serious damage, and it also needs to be completely thawed to be worked on.
Once you’ve turned the AC off, let it sit and thaw for 4–6 hours, then try changing your filter. A dirty, clogged filter will restrict airflow, making it a common culprit for a frozen AC. However, you should also consider the MERV rating of the filter you’re putting in, as filters that are too thick for your HVAC system to properly push air through can also cause freezing.
Our technicians typically recommend MERV 8 filters for residential homes. However, there’s no one-size-fits-all rule, and needs can vary from house to house. If you have questions about what kind of filter would work best for your HVAC system and lifestyle, consult a licensed technician for a personalized recommendation.
After you’ve changed your filter, turn your AC back on, then keep a close eye on it. If it freezes again, that means you’ll most likely need to turn to a professional to solve the root problem.
Another thing homeowners can do to improve their AC unit’s airflow is to clean visible dirt off the outside of the compressor. You can do this by simply hosing the fins down with a thumb over the hose’s opening to slightly increase water pressure. Don’t worry about damaging the compressor this way–these units are designed to withstand the elements. However, don’t use a power washer, as that level of pressure is likely to cause damage.
It’s good practice to hose down your AC compressor at least once a year, especially if you live in a part of Utah with lots of cottonwood trees. Cottonwood fluff gets everywhere in the spring and early summer, and it’s not uncommon for it to clog up AC units.
When to Call a Professional to Fix an Air Conditioner Frozen Over
Calling an HVAC technician is necessary to fix problems involving low refrigerant in your AC system, since handling refrigerant requires a license. If your system is low, a technician can check for leaks, repair them, and top off the unit.
If a more serious equipment failure turns out to be the cause of your frozen AC, get a quote from an honest, dependable HVAC service and repair contractor. Don’t be afraid to get a second opinion, as the repairs you buy can determine the comfort of your home for years to come.
Whichever route you choose, make sure to turn off your frozen AC system and let it thaw completely before your technician arrives.
CSA HVAC Services Provides Quality HVAC Service and Repair
At CSA HVAC Services in Orem, Utah, we believe in providing honest, quality service, helping our community, and treating our customers like family. If you’ve found yourself without reliable cooling this summer, our responsive team is ready to help get you back on your feet.
Our locally-owned business covers the greater Central Utah area, including Salt Lake County, Utah County, and neighboring cities. For HVAC repairs, maintenance, and installation you can trust, call (801) 874-5686 or fill out the contact form here on our website and schedule your free consultation today!