Window Air Conditioner: Water leaking inside house

If water is leaking into the room from the air conditioner, adjust the air conditioner so the back of the unit is slightly lower than the front, to allow the condensate water to drain outdoors. Level the air conditioner according to the guidelines in the installation manual. The air conditioner can also leak into the room if gaps around the window let warm, moist into the room, where it can condense on the front of the air conditioner. Seal air leaks in the cabinet or around the window opening. For more suggestions for preventing the air conditioner from leaking into the house, see the following.

window air conditioner

These repairs may help solve your window air conditioner problem

Level the window air conditioner

Level the window air conditioner

The back of the air conditioner should be slightly lower than the front so condensate water drains outdoor. If water drains into the room, reinstall the air conditioner so it tips backwards slightly.

Clear a window air conditioner clogged condensate drain

Clear a window air conditioner clogged condensate drain

Many (but not all) window air conditioners have a drain hole in the back to let condensate water drain outdoors. If the drain hole is clogged, clean the base of unit and clear the clog in the drain hole.

Symptoms for window air conditioners

Choose a symptom to see related window air conditioner repairs.

Main causes: bad compressor, lack of refrigerant, bad compressor start relay, electronic control board failure
Main causes: turning the air conditioner off and the back on too quickly, dirty or restricted condenser coil, compressor failure
Main causes: dirty air filter, air conditioner is too small for the room, temperature set too cold, control failure
Main causes: clogged drain hole, air conditioner not leveled properly
Main causes: clogged condensate drain, air conditioner not leveled properly, leaky window air seals
Main causes: lack of electrical power, bad electronic control board, wiring failure, bad temperature sensor

Repair guides for window air conditioners

These step-by-step repair guides will help you safely fix what’s broken on your window air conditioner.

How to replace a window air conditioner ambient thermistor

If your window air conditioner isn’t cooling properly, it might need a new ambient thermistor. You can replace it yourself following these instructions.

Repair difficulty
Time required
 45 minutes or less
How to replace a window air conditioner user interface control board

Control buttons or lights on the user interface control board can stop working. This repair guide shows how to replace it.

Repair difficulty
Time required
 30 minutes or less
How to replace a window air conditioner electronic control board

The electronic control board is the brain of your window air conditioner. Here’s how to replace it.

Repair difficulty
Time required
 45 minutes or less

Articles and videos common to all room air conditioners

Use the advice and tips in these articles and videos to get the most out of your window air conditioner.

September 26, 2019

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