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AC Unit Freezing Up
in Clarksville, TN
Clarksville sits in a humid part of Tennessee, and the air carries a lot of moisture from late spring through early fall. That moisture lands on your evaporator coil every time the system runs. When something goes wrong with airflow or refrigerant, the coil drops below freezing and that moisture turns to a block of ice. A frozen coil can't cool the house, and running the system in that state can burn out the compressor.
Quick Answer
A frozen AC unit happens when airflow drops too low or refrigerant runs short, and the coil gets so cold that moisture in the air turns to ice on it. In Clarksville's humid summers, that ice builds fast. Turn the unit off and let it thaw, then find the cause before you restart it. Call (931) 263-0432 to have it inspected.
Telltale Signs
Warning Signs to Watch For
- Visible ice or frost on the copper refrigerant lines outside
- Ice buildup on the indoor air handler or coil cover
- Water puddles or water stains under the indoor unit after the ice melts
- Airflow from vents drops to almost nothing
- The system runs for a long time but the house gets warmer instead of cooler
Root Causes
What Causes AC Unit Freezing Up?
Clogged or Blocked Air Filter
A dirty filter chokes off the airflow the coil needs to stay above freezing. Many Clarksville homes built in the 1980s and 1990s have return vents in hallways that get blocked by furniture or closed doors, making the problem worse.
The Fix
Filter Replacement and Airflow Check
Replace the filter and check every return vent for blockage. A technician can also measure airflow across the coil to make sure the system is getting what it needs.
Low Refrigerant from a Leak
When the refrigerant charge is low, the pressure inside the coil drops too far and the coil temperature falls well below freezing. Clarksville homes that were built before 2000 often still have older copper line sets with fittings that develop small leaks over time.
The Fix
Leak Repair and Refrigerant Recharge
The technician finds and seals the leak, then recharges to the manufacturer's spec. The coil will thaw and return to normal operating temperature once the pressure is correct.
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 or Blocked Air Filter | Low Refrigerant from a Leak |
|---|---|---|
| Ice appeared shortly after you changed nothing in the house | ||
| Filter was visibly gray and clogged when checked | ||
| Airflow from vents was already weak before freezing started | ||
| Unit has frozen more than once this season | ||
| Water pooled under the air handler after ice melted |
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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