Why is my Air Conditioner Freezing Up?

by | Aug 3, 2018 | Air Conditioner

AC Unit

A freeze up is when a layer of ice forms on the outside of your AC unit. Whether you have a window unit or a central air system the causes and effects of this, as well as the solutions, are the same. The ice build up on your AC unit creates an inability to cool effectively, and puts stress on the compressor, which in time can lead to a costly repair or the need for a replacement compressor.

There could be a number or reasons for this, at Phoenix Air Conditioning & Heating we would like to walk you through a few.

Insufficient Air Flow:

Anything that restricts the air flow in your unit will cause the system’s evaporator coil to freeze up. There are a few reasons that air may not be flowing efficiently. The most common problem is a dirty air filter. If you are running your AC unit continuously, we recommend replacing or cleaning the air filter once a month. Other air flow problems include blocked or closed ducts and vents, a faulty fan and/or dirt on the evaporator coils. Evaporator coils need regular cleaning, we recommend this once a season.

Low on Freon:

Another thing that causes an AC freeze up is low refrigerant or Freon. This causes a drop in pressure in the evaporator coil which then allows moisture in the air to accumulate and freeze on the coil. Low refrigerant or Freon is caused by a leak. If the cause of your freeze up is a low refrigerant you need to contact Phoenix Air Conditioning & Heating and one of our certified technicians will assist in the repair. This includes finding and repairing the leak and refilling your refrigerant levels.

Outdoor Temperature:

Air conditioners are designed to run in a specific temperature range. Most of them will not run well below 60°F. Often a freeze up occurs because night-time temperatures are dropping too low for the unit to function properly. When the air is too cool the pressure inside the system will drop and will cause a freeze up.

Call us today or schedule service online.

Need HVAC Service?

Contact the HVAC experts at
Phoenix Air Conditioning and Heating today!


Phoenix Air Conditioning & Heating services San Juan Capistrano, Lake Forest, Ladera Ranch, Laguna Hills, San Clemente, Dana Point, Mission Viejo, Irvine, Laguna Niguel, Laguna Beach, Aliso Viejo, Rancho Santa Margarita and the surrounding California communities with their heating and cooling needs. Visit our service area page for more coverage details, call us at 949-481-0204 or request service online today.

Pin It on Pinterest

3 Button Header

949-481-0204 949-481-0204

24-Hour Emergency Service Available!

FinancingEstimateRequest Service