When an air conditioner unexpectedly turns off and you can’t get it to work again, the culprit is often frozen AC coils. There are usually subtle signs that your air conditioner is frozen, and if ignored will lead to a total system shutdown and potentially irreversible damage to the compressor.

Early Signs of Frozen AC Coils

Running a frozen air conditioner can have dire consequences, so pay attention to these early signs of a frozen air conditioner:

• A decrease in cold air being produced and reduced airflow from vents.
• An increased amount of condensate drainage.
• Ice buildup on the outdoor refrigerant line or the evaporator coil.
• Condensation on the surface of the evaporator or condensate drain.

Why Do AC Coils Freeze?

There are usually two main reasons that AC coils freeze: there’s either restricted airflow in the system or there’s insufficient refrigerant.

Restricted Airflow

If air is restricted in any way throughout your cooling system, it could cause frozen AC coils. There are a number of instances throughout the process where the problem could originate, so it’s often a process of elimination to correctly identify the problem area. Start with the air filter and replace it if it’s dirty and clogged. Next, check that air ducts and registers aren’t blocked or closed. If these don’t fix the problem, a malfunctioning fan inside the air conditioner could be to blame.

Insufficient Refrigerant

Refrigerant is the cooling chemical that drives the air conditioning process. If there is a leak, not only will it cause your air conditioner to freeze and malfunction, it poses a safety risk. Only a professional AC technician has the certifications and training to safely handle cooling refrigerant.

 Unfreeze Coils

If you’ve located and fixed the problem of your frozen AC coils, you’ll need to take steps to de-thaw the coils.

• Turn off the AC breaker and allow the coils to thaw naturally.
• Remove any remaining moisture from the equipment before restoring power.
• Turn on ONLY the blower (or fan) to melt any additional ice clogging the coils.

If you weren’t able to find the source of your frozen air conditioner, schedule a service call  and let our professional cooling technicians diagnose the problem.

Fahrhall Home Comfort Specialists are fully trained, certified and prepared to meet all of your air conditioning service needs.