Why is My Old Air Conditioner Freezing Up?

Posted On: July 15, 2016
Air Conditioner

Do you have an older air conditioner that still uses R-22 refrigerant? You may have noticed that it has a tendency to freeze up from time to time. It’s a hard concept to grasp; the very piece of equipment that is designed to cool can actually become too cold. Ironic right?

A quick online search will tell you that a freezing air conditioner is caused by a refrigeration problem, and that is true.

Refrigerant leaks or low levels of refrigerant can cause pressure drops in the air conditioner’s evaporator coil, which allows the moisture in the air to freeze and accumulate on the coil.

When an air conditioner is low on Freon it’s still being expected to expand the same amount, but when the below par air flow isn’t blowing inside air over the evaporator coil then the required heat exchange won’t happen, resulting in Freon that should be removing heat from a home to fail from doing so. More expansion is what provides a cooler temperature.

That’s not all though.

There are two more common reasons why this can occur in air conditioners that use R-22:

  1. An air conditioner is ran without meeting specified temperature requirements.

    Air conditioners are made to run when the air outside is below 62 degrees. If the air conditioner is on when the outside air is below 62 degrees then the pressure inside the air conditioner drops, causing the air conditioner to freeze up.

  2. The AC system has experienced a parts failure.

    Like anything, an air conditioner has many parts that can break. Common part failures that result in a freezing air conditioner include a kink in refrigerant lines or a blower fan running out of balance.

Unfortunately, a frozen air conditioner isn’t a problem you should ignore. If you suspect that you have a frozen air conditioner you should address the problem as soon as possible. Have a professional air conditioning repair technician come out to help diagnose the problem.

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