How to Replace a Broken Motor on a Stalled Condensing Unit Fan

The condensing unit fan in your central air conditioner keeps air circulating to prevent the unit from overheating as refrigerant moves through the system. Overheating will cause the unit to shut down, and you won't have an efficient system or comfortable indoor temperatures.

If you don't hear the fan running at all, then the motor went out. If you or an air conditioning services tech have already removed the motor, putting the new motor on and putting the unit back together isn't complicated. If the motor isn't out of the furnace already, simply follow these instructions in reverse to get the old motor out first.

What You Need:

•    Screwdriver

•    New motor

•    Socket

•    Adjustable wrench

•    Zip ties

Step 1: Attach the New Motor

If you haven't already, turn off all electricity to the unit before beginning. This tutorial assumes that the fan guard was already detached from the condensing unit and the access panel on the unit is open. If these factors aren't right, just unscrew the fasteners attaching both to the unit and remove. Set the fan guard flat on a work surface to begin.

You should have the old wire conduit from the original motor. Slide the old conduit over the new wires until you reach the motor. Twist in a counterclockwise direction to tighten the conduit in place.

Position the new motor on the fan guard using the mounting screw holes as guides. Insert the fasteners and tighten with a socket. Take the guard and motor unit back to the condensing unit but just sit the guard's bottom on the top of the condensing unit for right now. You need to attach the wires before you can put the guard back into place.

Step 2: Attach the Fan Assembly

Feed the wires through the hole on the inside of the condensing unit near the access panel and then through the access panel. Connect the run capacitor wires to the correct terminals and the wires to the contactor using orientation pictures you took while unhooking everything or your owner's manual. Attach the wires simply by pressing down firmly until the wire snaps in place.

Position the hole of the fan blade over the motor shaft. Press down while wiggling to thread the fan blade over the shaft until the blades sit on the bottom. Use an adjustable wrench to tighten the set screw on the fan blades to secure.

Flip the fan guard and motor back over so that the motor faces down. Position the guard in its housing on top of the condensing unit using the mounting screw holes as a guide. Attach the mounting screws around the periphery of the guard to secure.

Step 3: Restore the Rest of the Unit

Move back to the wires you hooked up to the contactor and capacitor. Use zip ties to bundle up those wires to make the area neater and easier to access in the future.

Align the access panel door back into position using the mounting holes as a guide. Attach the fasteners to secure the door. Restore power to your unit then conducts a test run to see if the problem is fixed and if the fan is operating properly. If the problem persists, call an AC repair company like Weather Control Air Conditioning, Inc. for assistance.