Why is my window AC unit leaking water inside my house?

6/3/2022 (Permalink)

Building with multiple window AC units.

Question: I just turned my window AC unit on today and it is leaking water inside my house. What could be the problem? I had it running for 3 weeks and all of a sudden it started to leak. Water is on the plastic vent where the cold air blows out. I believe that is where it is leaking from but not sure. Can you tell me how to fix this? 

ANSWER: You need to check a few things to be sure the ac unit is installed properly and there is no water drainage block present.

– Unplug the window AC unit.

– Clean up all the water on the AC unit, on the window ledge, and on the floor of your room.

– Check and be sure the AC is tightly sealed in the window.

– Do you feel warm air coming into the room around the AC unit?

– If you feel warm air coming in you need to seal it again.

– Check to see if the drain holes on the rear of the ac unit are blocked.

– Clean the drain holes to allow water to drip out.

– Make sure the filter is clean and not clogged with massive dirt or dust.

– After cleaning up the water and having it turned off for 30 minutes or so, then turn it back on to make sure the water doesn’t appear again.

Here are the reasons water can drip from a window air conditioner unit:

AIR LEAK – AIR CONDITIONER NOT PROPERLY SEALED IN WINDOW:

If your window air conditioner is not sealed correctly, the warmer air from outside gets inside the air conditioner. When this happens, the moisture that is in the warmer air will be condensed by the colder air inside the air conditioner. When there is excess moisture, the water will leak. 

DRAIN IS BLOCKED – DIRT OR DUST HAS BLOCKED THE DRAIN HOLES:

There are drain holes (drip pan) at the rear of window AC units. They can get blocked from dusty conditions or dirt in the air. When this type of blockage happens, the water that would normally drip out will be trapped and water will leak from the front of the AC unit and at both sides of the unit. Be sure to keep the drain holes clean and free of debris. Also clean the filters or replace them to prevent any type of blockage that may cause a water leak.

OUTSIDE TEMP IS LOWER – HEAVY MOISTURE IN OUTSIDE AIR:

If it is raining or there is heavy moisture in the air outside, water evaporates much less than usual. This leads to excess water moisture in the air conditioner and this will cause water leaks. This is normal for most window AC units and using a drip pan can solve the issue if there is heavy moisture in the air outside.

CONDENSER PUMP NOT WORKING – BROKEN OR CLOGGED PUMP:

If the condenser pump in the AC is faulty or clogged, it will cause water to leak. You can check the condenser/pump if you feel confident. Check for any blockage or loose wires. If the pump seems to be okay visually, you will need to test the pump with a meter to see if it is faulty. If so, you may be better off buying a new AC unit.

If your home has experienced any water damage, the team at SERVPRO® is always available to help with cleanup and restoration, making it look “Like it never even happened.” Contact us at 908.650.8611.