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AC Unit Leaking Water Inside
in McKinney, TX
The indoor part of your AC pulls moisture out of the air and that water has to drain somewhere. In McKinney, humidity in July and August can sit above 70%, so the system pulls a lot of water out every day. When the drain line clogs or the drain pan cracks, that water ends up on your floor or in your ceiling instead.
Quick Answer
Water leaking from the indoor unit usually means a clogged drain line or a cracked drain pan. McKinney's humid summers put a lot of moisture into the system, and drain lines clog with algae several times faster here than in drier climates. Left alone, this water damages ceilings, walls, and the air handler itself. Call (361) 317-6400 before the water gets into drywall or insulation.
Telltale Signs
Warning Signs to Watch For
- Standing water or a wet spot on the floor under the air handler
- Water stains on the ceiling below a second-floor air handler
- A musty smell near the indoor unit or from the vents
- The AC shuts off by itself even though it wasn't set to
- Visible rust or water staining on the outside of the air handler cabinet
Root Causes
What Causes AC Unit Leaking Water Inside?
Clogged Condensate Drain Line
The drain line carries water from the drain pan out of your home. Algae and mold grow in the line because it stays damp, and in McKinney's humid summers the line can clog completely in a single season without maintenance. When it clogs, water backs up into the pan and eventually overflows onto whatever is below the unit.
The Fix
Condensate Drain Line Flush
A tech clears the clog using a wet vac or pressurized flush and checks the full length of the line. Many McKinney homeowners have a float switch installed that shuts the unit off before it overflows, and a tech can add one if yours doesn't have it.
Cracked or Rusted Drain Pan
The drain pan sits under the evaporator coil and catches condensation. In systems that are 10 or more years old, the pan can rust through or crack, and water goes straight through it. This happens in McKinney homes with older systems that have never had the pan inspected or replaced.
The Fix
Drain Pan Replacement
A tech removes the damaged pan and installs a new one. A temporary epoxy patch can slow the leak, but it doesn't last and the pan should be replaced properly.
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 |
|---|---|---|
| AC shuts off on its own and there's water in the pan | ||
| Water overflowing the pan and drain line appears clear | ||
| Musty smell from vents and slow water buildup under unit | ||
| Visible rust or hole in the bottom of the drain pan | ||
| Water on floor even when humidity is low outside |
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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