Replacement of an Air Conditioner Capacitor?

Has your air conditioner stopped working completely? Is there no air blowing from the grilles?

These faults can be due to a faulty capacitor.

What Is a Capacitor?

Some air conditioners in your home have capacitors for starting various motors in the system. Capacitors are like little batteries that store electrical energy and provide the initial 'jump-start' needed for air conditioners to get the motors up and running. Your air conditioning unit has three motors - compressor, indoor fan and outside fan - that all need to be powered using capacitors when they start.

Depending on what model air conditioner you have and whether it's a split or central air system, you may have either one capacitor to power all three motors or multiple capacitors powering each one individually. Either way, these air conditioner capacitors are essential for making sure your air con unit keeps running cool.

Signs of a Faulty Capacitor

Your air conditioner's capacitor is one of the most critical components. It helps to start your air conditioner . Without a functioning capacitor, your air conditioner won't work properly or at all. Unfortunately, capacitors can fail over time due to normal wear and tear or due to a power surge. Knowing the signs can help you avoid a costly repair bill due to a faulty capacitor.

Here are the most common signs of a faulty capacitor:

Strange Buzzing Noises

Got an awful buzzing coming from your air conditioner ? Chances are, it's a bad air conditioner capacitor. Unfortunately, these pesky capacitors can cause the AC unit to malfunction. It emits loud and strange buzzing noises when it is turned on. It's essential to address this issue as soon as possible, as the problem could get worse.

AC Unit Not Turning On

If you've come home from a hot day only to find that your air conditioner won't turn on, it's possible that one of your air conditioning capacitors has failed. The air conditioning capacitor plays a crucial role in starting the air conditioner motors, and without it, your AC won't run. Thankfully, this is an easy fix. Simply have the air conditioning capacitor replaced by a professional, and your unit will be restored to its former glory.

Not Enough Cool Air

If your split system air conditioner isn't blowing out enough cool air, it's possible that the capacitor could be failing. When this occurs, it can start the AC but not provide sufficient power for it to work correctly. This means that your system is running inefficiently, which will only make the issue worse because it won't be able to blow out nearly enough cool air. Getting a professional inspection and repair may be your best bet.

Shuts Down on Its Own

When your air conditioner starts shutting down unexpectedly, it's possibly due to a failing condenser fan motor capacitor. Without the condenser fan motor running, air can't flow through the condenser coils and the air conditioner will cut out on the high pressure safety. While it's possible that you can get away with just replacing the capacitor, the condenser fan motor should also be checked. Replacing the capacitor will result in your air conditioner functioning properly again.

Increasing Energy Bill

Air conditioning units running inefficiently due to a failing capacitor can have a bad result. The most obvious is lack of performance and no cooling effect.

Steps To Replace an Air Conditioner Capacitor

Replacing of a capacitor should only be carried out by a qualified technician. It is essential to understand the risks associated with working on an electrical appliance and with taking all necessary safety precautions. Qualified technicians are away of these and carry out the work in a safe manner.

That's why following these steps is the best way to ensure a safe and successful replacement of your air conditioner capacitor. You can also avoid air conditioner repairs in the future and possibly save yourself some money.

Here are the steps to replace an air conditioner capacitor:

1. Shut Down the Power

Locating and turning off the relevant circuit breaker will enable the technician to safely carry out the electrical works required.

2. The Correct Size Capacitor Must be Installed

Capacitors come in many sizes. They are rated in Micro farads. The correct sized capacitor is important to enable is to start the relevand motor it is required to start. Capcacitors come in a range of not only sizes but also what they are used for. eg Start capacitor, run capacitor and a combined run/start capacitor. An incorrect capacitor will not enable your air conditioner to operate correctly

4. Remove and Label Wires

Each ac unit has unique electrical wiring. The technician must take note of the existing wiring prior to removal of the faulty capacitor. Once this is done, the faulty capacitor can be removed. Installing the new capacitor in the air conditioning system is a reversal of the removal .Mount the new capacitor in the same location as the old one. It is impoertant to sensure the electrical wiring is reconnected the same as it was wired initially.

5. Install the New Capacitor

Installing the new capacitor in the air conditioning system is a reversal of the removal .Mount the new capacitor in the same location as the old one. It is important to sensure the electrical wiring is reconnected the same as it was wired initially. Once this is done, the air conditioner is ready to be turned back on.

6. Turn On the Unit and Test

The air con installation is nearly complete - all that's left to do is make sure it works properly. When you're ready, flip the main switch and give your air conditioner a test run. If anything seems off - like sparks or overheating components - hold off on running it until you've identified and rectified the issue. But if all looks good, then you can enjoy the cold air in no time! So go ahead and power up your air conditioner - here's to a safe and effective AC system!


Replacing your air conditioner capacitor is a simple and straightforward job that can be done easily by a qualified technicina. If all the necessary safety precautions are followed and the steps above carried out, you'll have a working AC unit in no time!

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