Why Your AC Unit Outdoors Has Ice On It And How To Solve The Problem

It's an odd sight when ice covers parts of your air conditioning unit when it's outside in the hot weather. However, icing over is a common problem with air conditioners and something you might encounter. Here's a look at why this happens and what to do about the problem.

Why An Air Conditioner Develops Ice

Ice forms on refrigerant lines when there is a reduction in airflow through the AC system, when the refrigerant is low, or when the evaporator coils inside are dirty. These problems interfere with the way refrigerant pulls heat out of your house and releases it outside. If the refrigerant gets too cold and the lines have condensation on them, the condensation turns to ice and the lines get even colder. This causes the ice to build until the problem shuts down your AC.

What To Do When You Find Ice On Your AC

Your first inclination may be to call an AC repair service, and that's a good first step. You may be told to turn off the AC and turn on the fan so the ice starts melting. An AC repair technician can't make repairs while the lines are coated with ice, so the first step is to let the ice melt. Ice can build up on the refrigerant lines outside and the coils inside the air handler indoors, so be sure to check both places.

While you wait for the ice to melt, you can check a few things to see if they're the cause of the AC trouble. Look at your filter to see if it's caked with dust. If so, that might be the source of the problem. Also, check both the indoor and outdoor units as well as the ducts for anything that could be obstructing airflow. It might be dust buildup, a curtain, or weeds around the condenser outside. If any of these problems are present, correct them, and your AC might work properly once it's turned back on.

How An AC Repair Service Might Solve The Problem

One thing the repair technician will check is the pressure level of the refrigerant. If the level is low, the next step is to track down the leak and repair it. Once the leak is fixed and the refrigerant is filled, your AC may work normally. Another thing the technician may check is the condition of the coil in the air handler. If it's dirty or excessively wet, the coil may need to be cleaned of dirt, have the mold removed, or have a drainage problem fixed that is keeping the coils wet. When the air handler is cleaned and dry, the coils can work properly and operate without creating ice.

The AC repair technician may also look at your system for things that reduce airflow. One culprit could be a blower that isn't producing much air. This problem may require cleaning the blower or repairing the motor that turns it.

A few things can cause your AC to ice over, and the cause should be corrected before you start up your AC again. If you don't, the ice may return.