A Little Leakage: Here's Why Your AC Might Be Dripping Water

A considerable amount of moisture is produced by your split system air conditioner. Condensation created by your unit occurs when warm air moves across the AC's refrigerant supply, although the level of moisture resulting from this process should be manageable, from your AC's perspective. The created moisture will be expelled by the unit's condensate drain line (located in the outdoor component of a split system unit). What does it mean when moisture is expelled from other parts of your AC?

Hanging Droplets

You may notice moisture forming on the casing of a split system AC's outdoor unit. A small amount of liquid isn't out of the ordinary on a hot day and is related to the temperature difference between the unit and the air outside. This should only ever be a small amount—hanging droplets of water at most. 

Indoor Evaporator

You could also note (with some alarm), moisture leaking from the unit's indoor evaporator, which is the primary section of the unit and is mounted to your wall. If this should occur, immediately deactivate the unit and place newspaper or a towel on the floor immediately beneath the evaporator. Any leakage may continue temporarily after the unit has been switched off. Move furniture out of the way as needed. 

Condensate Drain Line Blockage

Take a look at the outdoor section of the unit. The condensate drain line should be a copper or PVC pipe. Check to see that its drainage is unimpeded. Is the external end of the line in standing water? This is a distinct possibility in inclement weather, and unless the pipe is allowed to freely drip, moisture can look for other ways to escape, which can account for leakage from the unit's indoor evaporator. If possible, clear any blockage from the end of the condensate drainage line.


After removing the potential cause of moisture backing up inside the unit, you'll need to remove that moisture from inside the indoor evaporator. This is an automated function. Most split-system air conditioners feature a dry or dehumidification mode (check the remote control). Activate this mode and run the air conditioner at its optimal temperature. Periodically inspect the evaporator, checking for when moisture has stopped dripping. 

Further Steps

The automated dehumidification mode should dry out the evaporator and prevent further leakage. If these steps appear to have no effect, deactivate the unit. Arrange for professional air conditioning repair, as the unit is creating excessive internal condensation which is leaking out. The source of the issue must be traced and repaired.

A small amount of moisture should leak from your AC at the appropriate location. Anything more than a small amount (or when it leaks from an unexpected part of the machine) warrants further checking, and possibly professional repairs. For more information on AC repair, contact a professional near you.