Is It Normal for My Air-Conditioning System to Freeze Up?

air conditioner

air conditioner

An air conditioner freezing is not exactly uncommon, so when you see the inside of your unit coated in ice, do not fret. You might be thinking that your air-conditioning system operates to cool and condition the air when it is hot, so why is it freezing? Surely, it might seem weird, but it is common and can occur for various reasons.

Frost on Your AC’s Evaporator Coils

When you air-conditioning system freezes, you will see ice or frost around or on your unit’s evaporator coils. The evaporator coils of your unit hold cold refrigerant inside. When hot air from your house is moved over the evaporator coils, the hot air heats up the coils, which absorb it. This process also gets rid of moisture from the air and drips off the evaporator coils, turning the hot air into condensation. If your air-conditioning unit malfunctions and the evaporator coils cannot absorb sufficient heat, condensation will continue building up instead and freeze over since the refrigerant inside the coils cannot heat up as it is supposed to. This then will lead to the evaporator coils being covered with frost. But how exactly can this happen? You might find more detailed information from websites such as

Blocked Airflow

Your AC unit can freeze when there is insufficient return air that can be moved to the evaporator coils. As mentioned above, heat that the coils absorb is sourced from hot air from your house. If the airflow is blocked, usually due to filthy air filters, blower motor issues, or closed air registers, the coils will not have enough heat for warming up.

Insufficient Refrigerant

man fixing AC

The refrigerant held inside the coils is actually responsible for absorbing heat and transferring it outside. When there is a leak in the refrigerant, it will not be able to do its job properly. This, in turn, will lead to the coils remaining cold and eventually freezing over.

Freezing Weather Outside

This can be an issue during spring season when temperature levels can easily fall and rise erratically. In the event that your AC unit is turned on when the outside temperature falls below 60 degrees Celsius, the evaporator coils can easily freeze over.

Filthy Evaporator Coils

Dirt buildup on the coils will create an additional layer between the refrigerant inside them and the hot air moved over them. This additional layer will make it more difficult for the heat to move between the coils and the air, which, in turn, will cause the coils to stay cold and later on freeze up.

While strange, a frozen air-conditioning unit can easily be caused by the things mentioned above. In order to avoid this issue, make sure to have your air-conditioning unit inspected and cleaned at least every three to four months. Regular checks and maintenance will help you avoid more expensive repairs later on and extend your AC system’s service life. Do not forget to clean the air filter regularly, change it as needed, and keep air registers unblocked and open to prevent problems with airflow.

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