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AC Freezing Up
in McKinney, TX
When ice builds up on your indoor coil or the copper lines running to your outdoor unit, your AC has stopped working right. It happens most often in McKinney during the hottest stretches of summer when the system is running the hardest. Running a frozen unit can damage the compressor, which is an expensive part to replace.
Quick Answer
A frozen AC is usually caused by low airflow or low refrigerant, both of which drop the coil temperature below freezing. This is common in McKinney homes where filters go unchanged and vents get blocked. Turn the unit off and let it thaw before running it again. Then call (361) 317-6400 so a tech can find out why it froze in the first place.
Telltale Signs
Warning Signs to Watch For
- Ice visible on the copper refrigerant lines coming out of the indoor unit
- The air handler is running but little or no air comes from the vents
- Water dripping or pooling under the indoor unit after the ice melts
- The outdoor unit runs but the house won't cool down
- A thick layer of frost on the coil visible when you open the air handler
Root Causes
What Causes AC Freezing Up?
Clogged Air Filter
The coil needs a steady flow of warm indoor air passing over it to stay above freezing. A clogged filter chokes off that airflow and the coil temperature drops until ice forms. In McKinney, where systems run from April through October, a filter that should be changed every 30 days sometimes goes 6 months without being touched.
The Fix
Filter Replacement and System Inspection
Replace the filter and let the coil thaw completely before restarting. A tech should check the coil for damage and make sure airflow is fully restored before you run the unit again.
Low Refrigerant From a Leak
When refrigerant is low, the pressure inside the coil drops and the coil gets much colder than it should. Moisture in the air then freezes onto it. Many McKinney homes have older systems that have developed small refrigerant leaks over years of use, and a freeze-up is often the first sign the homeowner notices.
The Fix
Leak Detection and Refrigerant Recharge
A tech uses leak detection equipment to find the source, repairs the leak, and recharges the system to the manufacturer's specification. The coil needs to be fully thawed before refrigerant work begins.
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 | Clogged Air Filter | Low Refrigerant From a Leak |
|---|---|---|
| Ice on lines and filter is gray and clogged | ||
| Ice on lines and filter looks clean | ||
| Unit freezes up even after new filter installed | ||
| Water pooling under the air handler after thaw | ||
| Hissing sound near coil or refrigerant lines |
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