Window air conditioner symptoms

When your window air conditioner is running but not cooling, not running at all or leaking water inside the house, you'll need to take action fast. Our symptoms and troubleshooting solutions guide you through the steps to fix any window air conditioner failure. Get the repair parts you need by entering the part number or your air conditioner model number in the search bar. Follow the steps in the window air conditioner repair guides to install replacement parts and get the AC working again.

window air conditioner

Symptoms common to all 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: 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
Main causes: clogged drain hole, air conditioner not leveled properly
Main causes: dirty air filter, air conditioner is too small for the room, temperature set too cold, control failure

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 condenser fan

If the condenser fan blade is broken or the condenser fan motor won’t run, you can replace the broken parts yourself by following these instructions.

Repair difficulty
Time required
 90 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 for window air conditioners

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

January 29, 2015

Window air conditioner myths busted

By Sears PartsDirect staff

Let's clear up some misconceptions about room air conditioners.

January 6, 2015

Troubleshooting a leaking room air conditioner

By Sears PartsDirect staff

Learn why water leaks from a room air conditioners and how to fix it.

January 1, 1970

How to tell if a fuse is blown

By Lyle Weischwill

Learn how to tell whether a fuse is blown