Central Air Conditioning Capacitor Installation

Walk outside the home to where the main AC condenser unit is located. Look at the side of the home behind the unit for a metal box, which houses the fuse for the condenser. Open the box and grasp the fuse handle to pull it out completely. Note that some fuses have switches that flip up and down.

Locate the unit's access panel, which is attached via screws. Use a screwdriver to remove all of the screws, and set them in a safe area. Pull the access panel off and set it aside as well.

Peer into the unit until you identify the capacitor, which looks like a metal cylinder with wires attached to terminals at the top. The other end of the wires attach to the air conditioning compressor. Draw a diagram of the existing connections and the colored wires that go to each so that you can reattach the wires in the same configuration.

Detach the old capacitor by tracing the wires on top to the location they connect to the air conditioning compressor. Remove the screws that hold the wire prongs in place, and then pull the capacitor free from the unit. Some capacitors also have metal mounting straps wrapped around them that require additional screw removal to detach.

Refer to the diagram and install the top wires of the new capacitor to the same connections on the compressor. To connect the wire ends, align the holes on the wire ends with the holes on the unit and insert the screws until tight.

Wrap the mounting strap around the new capacitor, if applicable, and reinsert the screws there.

Place the access panel back on the AC unit by reinserting and tightening the screws. Replace the fuse in the wall box, or flip the switch back to the on position.