Why Does an Air Conditioner Freeze?
It might sound counterintuitive, but AC units do freeze over in south Florida. However, sometimes you can see the ice and sometimes you can’t. If you only feel a minimum amount of air flowing when you put your hand near a supply register, then your unit may be frozen.
If this has happened:
- Turn off the AC.
- Call in the professionals. Trained professionals will help with suctioning out any water in the ducts with a wet-dry shop vac and finding the reason your unit iced over. This can be done by a knowledgeable homeowner, but based on the usual reasons for a unit icing over, it’s best to have a trained technician on hand from the beginning.
What causes an AC to freeze?
There are a variety of reasons that your AC unit could freeze:
- Refrigerant levels are off: Whatever the reason for shifting refrigerant levels—a leak or something else—low refrigerant levels can make the evaporator coil too cold, which causes ice to form and build up on the coils. This can especially happen here in south Florida where the air is humid.
- Improper Airflow: An AC unit with improper airflow is one that is suffocating because it’s not getting sufficient air to operate. Like low refrigerant, low airflow will also cause the coils to freeze. The best way to help ensure this doesn’t happen is to regularly change/clean your filter.
- Thermostat problems: The unit can ice over if the AC unit is running all night unnecessarily.
- Supply registers: Be sure that no more than 25% of the supply registers are closed at any one time.
- Drainage issues: Drain blockages can cause the backed-up water to freeze all the way to the evaporator coil.
- Low fan speed: Low fan speeds don’t blow strongly enough across the evaporator coils).
Call American Air Cares if your AC unit is freezing over. Our state-certified, licensed, and insured air conditioning and heating specialists are here to help keep your AC unit in top working order.