How to Repair the Fan in Window Air Conditioners


When the fan on your window air conditioner stops functioning, you may be tempted to just go out and get a whole new unit. However, fixing the fan in a window air conditioner may be as easy as injecting its bearings with a healthy dose of penetrating oil-lubricant, or it may need replacing the motor assembly. Either way, the repair process is rather straightforward. Window air conditioners use low-cost fan motors that are constructed with welded casings. As a result, it is more cost-effective to replace these motors than it is to repair them.

Window Unit Fan Not Working: First Steps

Unplug the device from the power outlet, and then remove the screws that are securing the side accordion panels as well as the window unit. Because air conditioners are so heavy, you should ask a friend to assist you in removing the mounting screws while you work on the unit. Because of this, the device will be prevented from falling out of the window.

Slide the unit away from the window with the assistance of your assistant and place it on the floor so that you can work on it in a comfortable position. Remove the screws that are securing the case to the unit, and then slip the case off the device. When you are holding the case, use extreme caution since the edges of the sheet metal are very sharp and might cut you.

Clean and Check Fan Movement

Use a shop vacuum to clean the window unit itself before attempting to fix a window unit fan that is not functioning properly. If it includes a wand attachment, the regular vacuum you keep in your home may also accomplish the job.

By pressing the tip of the wand’s mouth against the openings at the motor’s case’s ends, you can ensure that the housing of the fan motor has been thoroughly cleaned out on the inside. It’s possible for grime, dust bunnies, and even hair from your pet to build up within the motor and prevent the rotor from freely rotating. If the air conditioner is turned on but is not producing any blowing air, the fan motor may be clogged with debris and not functioning correctly.

Next, you need to test to determine whether the blade of the fan can be turned easily by hand. Examine the fan to see whether or not the blades have been bent and are now causing friction with the shroud. When first started, these motors create a very little amount of torque, and even the smallest amount of dirt in the bearings or contact with the shroud that surrounds the blade will prevent them from operating correctly.

Check the Motor’s Bearings

If the fan blades were bent but the shroud that normally surrounds the blade was not loose, there is a good probability that the bearings in the motor are worn out and will need to be replaced. If you want to make sure the bearings are working properly, take the blade in your hand and attempt to move the shaft in different directions. Any movement that is noticeable indicates that the bearings are worn out, and the motor will need to be replaced.

If the blades were not bent, but they do not turn freely, a substantial amount of penetrating oil should be injected into the bearings. If doing that frees up the shaft and the blade so that it can spin freely again, you have probably saved yourself the expense of having to replace the motor. After plugging in the device, check to verify whether the fan is operating as it should. Before you replace the casing, make sure that the device is unplugged once again.

Replacing Fan Motor

Remove the connector that connects the wire harness of the motor to the control board. After that, unscrew the motor by removing the screws that are keeping it in place. Bring the old motor with you to the shop where you want to buy the replacement so that you can be sure to receive an identical match.

There are universal fan replacement motors available for purchase, which may be identified by their fractional horsepower rating and voltage; nevertheless, it is recommended that you pay a few more dollars to get an exact replacement motor. After you have replaced the motor and have reassembled the casing, you should then re-mount the unit in the window and plug it in.