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A Guide to AC Capacitor Replacement

The capacitor is an important part of your air conditioning system. When your AC kicks on, the blower fan motor, compressor fan motor and compressor motor all require a large amount of energy when they power on. The function of the capacitor is to supply a powerful electrical current to essentially jump-start these motors. An AC capacitor stores a powerful electrical charge, which it releases to allow the motors to start more easily. If the capacitor burns out or begins to fail, it can lead to hard starting. This is where the compressor turns on and almost instantly shuts back off. A bad capacitor can also cause the system to fail to start at all, and this can burn out any of the motors.

AC Capacitor Replacement

The capacitor is one of the few parts of an AC system that you can replace on your own, though if you’re not familiar with AC equipment, it’s best to leave it to a professional. If you’re experienced with air conditioners and home electrical maintenance, all you need to do is remove the access panel located at the back of the compressor, unhook the wires from the old capacitor and then rewire the new part in the same way. Before starting, it is essential that you turn off the electricity to your AC system and discharge the capacitor. Touching the capacitor when it still contains a charge can result in a major shock. As long as the power is turned off, the stored current won’t be enough to seriously electrocute you, but it definitely won’t be a pleasant experience either.

How to Discharge the Capacitor

After turning the power off, you can discharge the capacitor with an insulated pair of pliers or a screwdriver. Take your tool and lay it across so that the metal touches both of the capacitor terminals. This creates a connection between the two that instantly releases the capacitor’s stored charge. It is vital that whatever tool you use has an insulated handle or grip or else the current will flow through you when the electricity is discharged.

Finding the Correct Replacement Capacitor

You should be able to find the correct replacement part at your local home improvement store. When buying the replacement part, you need to check that the new and old parts have the same tolerance, voltage load and capacitance specifications. If the specifications aren’t the same, your AC probably won’t turn on. You also run the risk of damaging any of the AC motors if you don’t use the correct capacitor.

If you suspect your AC capacitor is beginning to fail, the expert AC technicians at McFarland Indoor Comfort Services can replace it for you and save you the hassle of doing it on your own. We repair and service all AC brands and any compressor model, and we will ensure that you get the exact replacement part you need. Our team also repairs, installs and services all types of heating equipment for residential and commercial customers in Granite City and throughout St. Clair and Madison counties. To schedule an AC service appointment, give us a call today.