How to Discharge an AC Capacitor

Multiple components in an AC work together to ensure you have a cool space, including AC capacitors. With all the work an air conditioner does, large capacitor components are necessary to ensure the system has sufficient energy.

As a safety precaution, you’ll need to discharge a capacitor when you need to work on some of the AC’s internal components. Therefore, always ensure you discharge an AC capacitor despite disconnecting the power. Thankfully, it’s a straightforward procedure.

This guide will help you learn how to discharge an AC capacitor safely. You’ll also learn why to hire a professional to help you do the job. Keep reading to learn more!

How Do You Discharge an AC Capacitor? 

The start and run capacitors are the ones you need to discharge before starting internal work in an AC. Usually, discharging an AC capacitor is necessary for your safety and to keep the capacitors from breaking down. 

Here is how to discharge AC capacitor connections like a pro.

  1. Cut Off Power Supply to The Air Conditioner

Turning off the circuit breaker is the first step to discharging an AC capacitor. You can find it on the main electrical panel. So, verify that the power is entirely off using a non-contact circuit tester. 

  1. Find The Capacitor 

The manufacturer’s manual can help you locate the capacitor. Its location may vary depending on the unit’s manufacturer. Usually, it’s directly on the motor or mounted on the wall in the interior. 

Remove the screws on the unit side panel to locate the capacitor to get to the primary assemblies. Use a screwdriver to dislodge the screws.

After loosening the screws, you may retrieve the side panel and set it aside. Proceed to ensure you have eyes on the capacitor without touching anything. Touching the components in the units before discharging the capacity could lead to electrocution.

  1. Use A Screwdriver to Discharge the Capacitor 

An insulated screwdriver is the best option when discharging a capacitor. An insulated screwdriver has a plastic or rubber handle. The insulation ensures that your hand doesn’t touch the metal part of the screwdriver.

  • Examine the screwdriver. Regarding insulation, ensure that the insulated handle is intact and without damage. Examine it to eliminate cracks and breaks. Buy a new insulated screwdriver if you have to guarantee your safety.
  • Grip the capacitor in your hand. Hold the capacitor on the base in one hand. Ensure that you hold it comfortably. The best thing is to make a “C” with your hands and fingers. None of your fingers should be at the top near the capacitor’s posts. It might be a good idea to have insulated pliers to hold other capacitors. 
  • Apply the screwdriver. If you have held the capacitor correctly with the posts pointing to the ceiling, it’s time to introduce the screwdriver using your other hand. Ensures contact between the capacitor posts and the metallic end of the screwdriver.
  • Listen and observe. You should watch and hear a spark showing the discharge is successful. The screwdriver has to touch both terminals on the capacitor simultaneously for this to happen.
  1. Confirm The Discharge 

It’s essential to confirm the discharge before proceeding to touch the capacitor with your bare hands. Use the screwdriver once more by retouching the two posts. 

The lack of a spark shows that it is discharged, and you can proceed to work on the unit. Apply other discharging tools like a multimeter to check for the discharge if you prefer to take extra caution.

Reasons To Let a Professional Discharge an AC Capacitor 

There is a danger of electrocution when discharging an AC capacitor. It’s not a challenging task, but it requires a certain level of precision to guarantee your safety.

A professional knows the right tools to use and how to apply them. Also, they would know what to do in case of electrocution.

Allowing an expert to discharge your AC capacitor leaves room for them to discover any issues your unit might have. Such problems may include a compromised capacitor that may pose safety issues. It may be costly, but it’s always better to let a trained professional work on your AC unit. 

Importance of Discharging an AC Capacitor  

An AC capacitor stores an electric charge even after cutting off the power supply to the unit. The amount of charge stored is enough to shock you as the capacitor discharges through your body.

Discharging an AC capacitor is, therefore, a safety matter. Ensure there isn’t a charge in your unit even though it was idle.

What Tools Can Discharge an AC Capacitor 

Although this post focuses on how to discharge an AC capacitor using an insulated screwdriver, there are other tools you can use for the task. They include:

Bleeder Resistor

A bleeder resistor is a capacitor discharging tool of choice for most professionals. It discharges capacitors after you remove the power supply to the circuit.

Some manufacturers install the circuit to automate the discharging process. The discharge rate using a bleeder resistor depends on the capacitance of an AC capacitor.

You can connect one yourself if your unit has no bleeder capacitor. All you have to do is connect the leads of a bleeder resistor to crocodile leads. Then, attach the crocodile clips to the capacitor and give it time to discharge.

Resistive Load 

The other alternative is to discharge an AC capacitor using a  resistive load. Again, tungsten is the best option. All you have to do is retrieve it from, say, an old lamp.  You are good to go as it has a good power rating.

Connect the capacitor’s leads to the terminals of the tungsten. The lamps should glow as the capacitor discharges. The light fades out when the capacitor finishes discharging.

Final Words

Figuring out how to discharge an AC capacitor using a screwdriver is easy. Pay attention to all the procedure’s essential details, including the screwdriver’s state. Watch where you put your hands as well. 

Use the manufacturer’s manual as a guide to the location of the capacitor. If you can’t discharge an AC capacitor yourself, it is always best to involve an expert. Again, it’s a matter of safety and preserving the condition of your ac. 

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