Why Is My AC Frozen? Ice on Your AC Lines or Coil Explained
It sounds backward, but an air conditioner can freeze solid on a 100 degree day. If you see ice on the copper line going into your outdoor unit or frost on the indoor coil, your system is telling you something is wrong.
What to do right now
Turn the system to OFF at the thermostat. Leave the fan on AUTO, or set it to ON to help the ice melt faster.
Let it thaw completely. This can take several hours. Place towels around the indoor unit because melting ice can overflow the drain pan.
Do not chip at the ice. You can easily puncture the coil or line.
Check your air filter while you wait and replace it if it is dirty.
Common causes of a frozen AC
Restricted airflow. This is the most common cause. A dirty filter, closed vents, blocked returns, a dirty indoor coil, or a weak blower all reduce the warm air moving across the coil. Without enough warm air, the coil gets too cold and moisture freezes on it.
Low refrigerant. When refrigerant is low due to a leak, pressure in the coil drops and the coil temperature falls below freezing. This needs a technician to find and repair the leak.
Blower motor problems. If the indoor fan is running slowly or not at all, the coil will ice over quickly.
Running the AC on cool nights. Running the system when it is cool outside, especially at a very low setting, can sometimes cause icing on certain systems.
When to call
If you replaced a dirty filter and the system runs normally after thawing, keep an eye on it. If it freezes again, call us. Repeated freezing can damage your compressor, which is the most expensive part of the system.
Call Red Rock Mechanical at (405) 305-3085 or book online. We serve Oklahoma City, Shawnee, Bethel Acres, and the surrounding areas.
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