Troubleshooting
AC Leaking Water Inside
Quick answer
Almost always a clogged condensate drain line. Pour 1 cup of vinegar through the cleanout port. If still leaking, the drain pan or P-trap may be cracked.
Common causes
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Clogged condensate drain
easyAlgae and biofilm build up in the PVC drain line → backs up → drain pan overflows.
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Cracked drain pan
moderateOlder units develop pinhole leaks in the metal pan. New pan needed.
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Frozen evaporator coil
moderateWhen ice melts, it overwhelms the drain. See AC freezing up.
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Disconnected drain line
easyPVC joints can pop apart. Check the run from the unit to the floor drain.
DIY first
- 1 Find the white PVC drain line from the indoor unit. There's usually a T-fitting near the unit with a cap — the cleanout.
- 2 Pour 1 cup of distilled white vinegar through the cleanout. Wait 30 minutes.
- 3 Run hot water through to flush.
- 4 Check the line where it exits the building or drains to a floor drain — make sure it's clear there too.
Call us if:
- Vinegar didn't clear it
- There's water-damage staining on the ceiling/wall near the unit
- The drain pan itself is rusty or visibly cracked
Other symptoms in this category
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