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AC Leaking Water Inside
in Lewisville, TX
Lewisville's humid summers pull a lot of moisture out of your indoor air, and that moisture has to go somewhere. Your AC collects it in a drain pan and sends it outside through a drain line. When that line clogs or the pan overflows, water ends up on your floor or ceiling instead.
Quick Answer
Water leaking from your indoor AC unit in Lewisville is almost always a clogged drain line or a frozen coil that's thawing out. The drain line — a white PVC pipe that carries condensation outside — backs up when algae builds up inside it. Don't let it sit. Water damage to ceilings and walls adds up fast. Call (361) 401-8806 before the drip becomes a flood.
Telltale Signs
Warning Signs to Watch For
- Standing water or a puddle under the indoor air handler
- Water stains on the ceiling below a second-floor air handler
- A musty or moldy smell coming from the vents or utility closet
- The AC shuts off on its own and won't restart
- The drain pan visible under the unit is full of water
Root Causes
What Causes AC Leaking Water Inside?
Clogged Condensate Drain Line
In Lewisville's humid summers, your AC pulls several gallons of water out of the air every day. That water drains out through a PVC condensate line. Algae and mold grow inside that line over time, and eventually it backs up and water overflows the drain pan. Many Lewisville homes built after 1995 have the air handler in the attic, so a backed-up drain line can pour water through the ceiling before anyone notices.
The Fix
Drain Line Flush and Cleaning
A technician flushes the drain line with a wet-vac or pressurized water, clears the blockage, and treats the line with an algae tablet to slow future buildup. The drain pan and float switch are checked at the same time.
Cracked or Rusted Drain Pan
Older air handlers — units from the early 2000s or before — have metal drain pans that rust through over time. Even if the drain line is clear, a cracked pan lets water leak out before it reaches the drain. This is a common finding in older Lewisville neighborhoods like Timber Creek Estates where original HVAC equipment hasn't been replaced.
The Fix
Drain Pan Replacement
The technician replaces the primary drain pan with a new one. If the secondary overflow pan underneath also has rust or cracks, that gets replaced too. A float switch is added if one isn't already installed, so the system shuts off before it overflows 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 | Clogged Condensate Drain Line | Cracked or Rusted Drain Pan |
|---|---|---|
| Water dripping from the air handler or ceiling below it | ||
| Drain line has no water flowing out during operation | ||
| Drain pan is full but drain line appears clear | ||
| AC shuts off on its own — float switch tripped | ||
| Rust stains or visible cracks on the drain pan |
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