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Why Ice on Your AC Is a Big Deal

Serving Families Throughout Dallas
ice on air conditioner evaporator coil

Have you ever noticed ice forming on your air conditioner? While it may look harmless, ignoring ice on your AC is a big mistake. Ice formation is a sign that something isn't working right and could be causing damage to your system. Here’s why ice forms on an air conditioner and what to do if it happens.

Why Ice Forms on Air Conditioners

When ice or frost forms on an air conditioner, it's almost always on the evaporator coil (the coil located indoors). Your system's blower blows hot indoor air over the evaporator coil. Meanwhile, the refrigerant in the evaporator coil absorbs heat from that indoor air, making it cooler.

Below are the three most common reasons why ice forms on air conditioners and evaporator coils.

Lack of Air Flow. When air isn't circulating properly, your AC's evaporator coil can become too cold. This causes condensation on the coil to freeze, resulting in a layer of frost or ice. Dust-clogged air filters are the most common culprits behind poor airflow.

Low Refrigerant Levels. It may seem counterintuitive, but a low refrigerant level can cause the evaporator coil to freeze. In a nutshell, if the refrigerant in an air conditioner is low, the pressure in the system will be low—which also means the temperature in the system will be low. Condensation can freeze on the evaporator coil if the temperature drops below freezing.

Dirty Evaporator Coil. If your evaporator coil is clogged with dirt and debris, it won’t be able to absorb heat from the air efficiently. When the evaporator coil cannot absorb heat effectively, the coil gets extremely cold, and the condensation collecting on it freezes.

Why You Shouldn’t Ignore Ice on Your Air Conditioner

A layer of ice may not seem like a big deal, but it's important to look at how this affects your air conditioner's ability to function. Once a layer of ice forms on the evaporator coil, that coil has a harder time absorbing heat from your indoor air. Consequently, the coil will get even colder, and more ice will form. The thicker the ice gets, the more it will restrict the warm air trying to move through the coil, worsening the problem.

Additionally, this freezing affects refrigerant's movement through your AC system, impacting its ability to change back and forth between liquid and gas. That change in state from liquid to gas and vice versa is crucial—not just for your AC to work but for it not to break down. If liquid refrigerant makes its way to the compressor (which is very expensive to replace), the compressor can be irreversibly damaged.

What To Do if Ice Forms on Your Air Conditioner

So, if we have not made it clear, do not ignore ice or frost on your air conditioner! Follow these steps instead:

  • Shut off your air conditioner, and let the ice thaw. This could take a few hours. A hairdryer can help speed up the process.
  • Do NOT try to scrape or hack the ice away. You will very likely damage your evaporator coil.
  • Meanwhile, check out your air filter. If it's dirty, replace it. If it isn't, check to see if its efficiency rating is too high for your system. Some older systems are not compatible with filters with high ratings.
  • Contact an HVAC technician to check out your AC, particularly the coils, blower fan, and refrigerant level. A motor issue could be preventing proper airflow through the system, and as mentioned above, a low refrigerant level may also be the problem.

Remember: continuing to run your AC when it has a layer of ice can result in irreversible damage to the compressor, which costs a pretty penny to replace.

24/7 Air Conditioner Repair in the Dallas-Fort Worth Metro

At Rescue Air and Plumbing, we are "Fast and Fair With Your Repair!" Our team is available 24/7 to respond to your air conditioner emergencies, whether it's ice formation on the evaporator coil or any other issue with your system. We proudly serve the Dallas-Fort Worth Metro area. Contact us today to schedule a service appointment: (972) 201-3253.