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AC Freezing Up
in Lewisville, TX
It sounds backwards, but your AC can freeze solid in the middle of a Lewisville summer. It happens when the evaporator coil — the part inside your home that cools the air — gets too cold. Left alone, ice blocks all airflow and can damage the compressor.
Quick Answer
A frozen AC in Lewisville usually means airflow is blocked or the refrigerant charge is off. When the coil gets too cold, moisture in the air freezes onto it and shuts the system down. Turn the unit off and let it thaw, then call (361) 401-8806 so a technician can find out why it froze in the first place.
Telltale Signs
Warning Signs to Watch For
- Ice or frost on the copper refrigerant lines going into the wall
- Little or no air coming from the vents even though the system is running
- Water pooling or dripping around the indoor air handler
- The outdoor unit runs but the house doesn't cool down
- A musty smell coming from the vents after the ice melts
Root Causes
What Causes AC Freezing Up?
Restricted Airflow From Clogged Filter
Your AC needs a steady flow of warm indoor air moving across the evaporator coil. When a clogged filter cuts that airflow off, the coil drops below 32 degrees and freezes. Lewisville homes with multiple pets or near open construction — like areas off FM 407 where new builds kick up a lot of dust — clog filters faster than most.
The Fix
Filter Replacement and Airflow Inspection
A technician replaces the filter, checks all supply and return vents for blockages, and confirms the system has enough airflow to run correctly. This is one of the easier fixes, but only if the coil itself hasn't been damaged.
Low Refrigerant Charge
When refrigerant pressure drops below the correct level, the evaporator coil gets colder than it should and frost builds up on it quickly. This is a common finding on systems more than 10 years old that haven't been serviced regularly. The fix isn't just adding refrigerant — the leak has to be found first.
The Fix
Leak Repair and Refrigerant Recharge
The technician locates the leak, repairs it, and brings the system back to the correct charge. Running the system with a known leak will just freeze it again.
Self-Diagnosis
Which Cause Applies to You?
Check the signs you're observing to narrow down the likely root cause before your inspection.
| What You're Seeing | Restricted Airflow From Clogged Filter | Low Refrigerant Charge |
|---|---|---|
| Ice visible on refrigerant lines or coil | ||
| Filter is visibly clogged or hasn't been changed in months | ||
| Water dripping from the indoor unit after thawing | ||
| System freezes again shortly after thawing | ||
| Airflow from vents is noticeably weak |
Free Inspection
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An on-site inspection is the only way to confirm which cause applies to your property. Free, no obligation.
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