Quick answer
Turn cooling off, switch the fan to On to thaw the ice, and check the filter. Don't chip at the ice. If it freezes again, call a technician — it usually means low refrigerant or an airflow problem.
Why your AC freezes
The indoor coil is meant to be cold, but not below freezing. When too little warm air passes over it — or there's too little refrigerant — the moisture on the coil freezes, and the ice can spread to the lines outside.
What to do right now
- Turn cooling off at the thermostat
- Set the fan to On so indoor air melts the ice — this can take a few hours
- Check the filter and replace it if it's dirty
- Open all supply vents and clear anything blocking the return grilles
- Watch for water — melting ice can overflow the drain pan
Once it's thawed
Turn cooling back on and keep an eye on it for a day. If the lines stay clear, a dirty filter or closed vents was probably the cause.
If the ice comes back
Recurring ice usually means low refrigerant (which means a leak), a failing blower motor or a dirty coil. These need a technician — adding refrigerant without finding the leak doesn't fix anything.
When to call a pro
- Ice comes back after it thaws
- Water is leaking around the indoor unit
- You hear hissing near the lines
- Airflow is weak even with a clean filter