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What Causes an AC to Freeze Up?

frozen evaporator coils
While you might think ice on your AC is a sign that it is working, it’s actually a sign that it needs to be repaired right away. During summertime, it is common for air conditioners to get overworked and experience malfunctions that can lead to frozen evaporator coils and other types of serious damage. At Lex Air Conditioning and Heating, we recommend becoming familiar with the most common causes of frozen ACs so that you can take the necessary steps to avoid this problem. Keep reading to learn more about why your AC might be frozen and what you should do about it.

Common Reasons for Frozen ACs

The evaporator coils on your inside AC unit contain refrigerant that is used to cool the air being sent into your home.

There are a variety of problems that can cause the evaporator coils on your AC to freeze up, including:

  • A lack of airflow: Your evaporator coils are filled with refrigerant, which is used to create cool air. Warm air is sent over the evaporator coils to simultaneously prevent the coils from freezing over and provide the coils with air that can be cooled and sent inside. When your AC’s airflow is restricted, the evaporator coils are not warmed by the air, which causes them to freeze over. A lack of airflow can be caused by clogged filters, broken or undersized ductwork, or a malfunctioning motor blower.
  • Low refrigerant levels: Low refrigerant levels can cause a drop in pressure in your AC. This pressure drop can cause the evaporator coil temperatures to drop below freezing, forming layers of frost until the coils are coated in ice.
  • Dirty coils: When your air filter is low quality or clogged, it can send excess dust into your air conditioner. This excess dust can build up on your coils until they are encased in them. This layer of dust acts to insulate the evaporators, which restricts airflow and causes the coil to freeze over.

What to Do If Your AC Is Frozen

If your outdoor AC unit is frozen, it is important that you call a qualified Carrollton HVAC repair technician right away. A frozen AC unit is a sure sign that something is wrong with your system and ignoring this issue could lead to a complete system breakdown.

While you wait for your HVAC technician to arrive, turn your thermostat off, but leave the fan on. Keeping your thermostat set to cool will force your system to endure more strain and increase the risk of further damage. Instead, setting the fan to “On” while keeping the cooling setting off can add airflow that can start to melt the ice on your AC.

Call Lex Air Conditioning and Heating Today

A frozen AC is a serious problem, but it can be fixed if it is early on. At Lex Air Conditioning and Heating, each of our technicians has undergone extensive training and is fully qualified to handle your every heating and air conditioning need. If your AC is frozen, we will be there in no time at all to discover the source of the problem and get your system back up and running.

Our air conditioning services include:

Backed by 30+ years of service excellence, you can count on Lex Air Conditioning and Heating to implement a reliable and lasting solution.

To learn more about how we can take care of your home, please call (972) 217-8955 or send us a message online.

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