3 Reasons your A/C Unit Could be Freezing Up

Air conditioners serve our living spaces greatly during a hot summer day. They cool our home’s interior air to create a comfortable environment and improve the house’s air quality.

Unfortunately, freezing up is a common problem in air conditioners and usually happens even during the hottest day of the year. If your AC freezes, its working principle does not allow it to make the air in your room any colder. Of course, that is terrifying since it can turn an elegant summer day into a blistering hot one within a short time.

This post gives you the three reasons why your AC could be freezing up and how you can address the problems.

1.    Low Refrigerant Levels

Chlorodifluoromethane is the refrigerant used in air conditioners and has different physical properties depending on pressure. Leakage in the AC unit is the major cause of low refrigerant levels. As the level drops, pressure decreases as per the Joule-Thompson Effect and ultimately leads to lower temperatures.

An AC functions through refined control of temperature, pressure, and airflow, where an imbalance of the three results in freezing up. Warm and moist air from your house condenses on the coils as it flows over the evaporator leading to frost build-up. The solution to this problem is to call an HVAC technician to assess leakage and check refrigerant levels in your AC.

2.    Inadequate Airflow

Lack of airflow is another reason behind the freezing up of air conditioners and can result from different malfunctions, including:

  • Blocked Air Filter

An air filter sits between the home vent and the air conditioner itself and keeps the air and your compressor coils clean. However, it may fill up with dust, causing clogging rather than providing a pathway. With a clogged filter, even a blower running at the highest efficiency won’t reverse the slowed airflow, and your unit will ultimately freeze up.

  • Inadequate Power to the Fan

Sometimes the power supply to the AC unit could be the reason behind the inadequate airflow. For example, an underpowered blower motor or fan may cause inadequate airflow even as the other compressor runs optimally.

  • Collapsed Duct

Collapse or blockage of air ducts in your home can stop the natural flow of air to the coils even when the rest of the system works properly. As a result, the coils start to freeze because they cannot receive adequate warm air to maintain them at optimal temperatures.

  • Defective Blower Motor

The blower motor has a huge role in an AC system. When it stops blowing, the airflow slows or comes to a halt, and the coils begin to freeze.
Any of the above malfunctions could be the reason your AC unit is freezing up. Therefore, you need a skilled HVAC expert to check the specific issue and rectify it.

3.    Blocked Coils

The evaporator coil is crucial within an AC unit. It removes excess moisture to reduce humidity in the house. AC coils are usually damp due to the moist air that condenses on their cold surface. When dust blows over them, it forms a thick blanket that acts as an insulator. This insulation traps excess cold inside the coils causing the AC unit to freeze up.  To address this issue, you should schedule regular checkups with an HVAC professional to clean the coils and prevent further damage to your AC unit.

Air conditioning unit problems are complex and require professionals to diagnose correctly and provide an expert solution. You can count on our more than five decades of experience in the industry to provide quality HVAC installation and repair services. Contact us today for all your HVAC needs.

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