Look for ice or frost on the outside copper pipes leading from the house to the AC, and on the pipes inside from the furnace leading to the outside unit. It can also form on the “A” coil. This is located right on top of the furnace inside a metal housing. There are two main reasons why your copper pipes or coils have ice on them.
Refrigerant is an important part of your air conditioner system. It collects the heat in your home and moves it outside.
Over time vibrations and normal wear and tear can lead to refrigerant leaks. This causes your AC system to work less efficiently and can also cause the air conditioner to freeze. This is one of the reasons we strongly advocate annual maintenance on your comfort system.
When an air conditioner is low on refrigerant, the coils containing the refrigerant get too cold, causing ice to build up on the coils. The problem grows quickly when the air is humid or the coils are dirty.
Improper Airflow is another reason for ice formation. This basically means that your air conditioner is suffocating and not getting enough air to operate properly.
Insufficient airflow causes the coils to drop below freezing. The humidity in the air then collects on the coils, creating an even greater buildup of ice on your air conditioner.
Insufficient airflow is usually a result of a dirty air filter that needs to be replaced, but can also be caused by:
- An air filter that is too restrictive
- Not enough return air ducts
- Improperly sized or damaged ductwork
- Dirty evaporator coils
The result of a frozen AC is that you may have air flow, but it is not cool air. If you have ice on your piping or indoor coil above the furnace, turn the system off immediately and call a professional service company. The ice must thaw completely before the system can be serviced.