Causes of Ice Buildup on Air Conditioners

Hi, I am Daniel with Comfort Zone of North Florida. Ice on an air conditioner is not normal, even in a Florida summer. It means the indoor coil got too cold, and the cause is usually airflow, refrigerant or a control problem. This post covers the causes. If you already see a frozen pipe and need the fix steps, read our frozen AC pipe solutions post.

1. Blocked Airflow

A dirty filter, closed vents or a dirty indoor coil can starve the coil of warm air. With too little warm air passing over it, the coil temperature drops below freezing and moisture in the air turns to ice. Check the filter first, open the vents, and do not scrape ice off the coil, because you can damage it.

2. Low Refrigerant From a Leak

Refrigerant is not consumed in normal cooling. Low charge means a leak to find and repair. Low charge also lowers coil pressure and temperature, which leads to ice. Our $99 diagnostic includes gauges and findings in writing before work starts.

3. A Failing Blower or Control Problem

If the blower runs too slowly or stops, or a control keeps the system running when it should not, the coil can freeze. The same is true if the thermostat is set very low on a cool night. Turn the system off if ice is heavy, let it thaw, and call us before running it again.

Minor repairs run $150 to $400, and compressor and coil replacement starts at $1,485. Our technicians are EPA certified, factory trained and NATE certified, paid hourly with no commissions, and we have served North Florida since 2009. Call Comfort Zone at (904) 406-0070. We are open 24 hours, 7 days.