Is It Possible To Replace AC Capacitor By Yourself?


The capacitor is one of the most important parts of an air conditioning system. Its primary function is for energy storage which it uses to jumpstart the fan and the compressor of the AC unit. If it malfunctions, it can result in serious system problems or cause the AC system to stop working.

Identifying a busted capacitor is actually easy. If the compressor is unable to start, it can suggest a faulty AC capacitor. Some units might attempt to run but only produce a humming noise and the compressor doesn’t proceed. The good news is that replacing the electrical equipment is relatively simple. With the right tools and basic handyman skills, YES you can DIY replace a blown capacitor.

How to Check Your AC Capacitor

Go to the condenser unit usually located outdoors. You can use a voltmeter to check if the capacitor is discharged. But even without this device, you can still check it by simply listening for a humming sound and watching if the fan is spinning. If the condenser is humming but the fan is static, then you can suspect a capacitor problem.

Try giving the fan blades a gentle push by sliding a long stick through the fan grate. If the fan takes off and runs, then it has a bad start capacitor. That’s the main function of the capacitor – give the fan motor a boost upon startup. If it is unable to do so, then the capacitor lacks sufficient electrical charge.

Other signs of capacitor breakdown include smoke with an acrid smell, chemical leaks out of the casing, bulging case, and intermittent startup failures. There are many possible reasons why your capacitor blows. A certified technician from Hartman, air conditioning installation company, lists some of the common causes of capacitor failure:

  • overheating motor,
  • extreme temperature,
  • sudden power surge,
  • normal wear and tear, and
  • physical damage such as from debris hitting the condenser unit.

Capacitor problem is the most frequent cause of a problematic AC fan, motor, or system as a whole. Knowing how to diagnose AC capacitor trouble and replace it can save you the hassle of looking for an AC technician and living without an air conditioner for days.

Steps for Replacing an AC Capacitor

The actual capacitor replacement is not difficult but requires good manual skills, basic electrical tools, and careful attention. Here’s a step-by-step guide on DIY capacitor replacement.

1.      Know your local regulations.

Working with electricity poses safety risks, be sure to check your local health and safety regulations for guidance and to avoid unwanted accidents. Make sure you have proper tools and safety gear before starting. If you are not confident with your skills, it’s best to call a certified technician.

2.      Locate the breaker box and switch power off.

Typically, the breaker box is located beside the condenser outside. Turn it off to cut the electric supply of the AC system. You can do a quick check if there is still power by using a voltmeter.

3.      Open the access panel of the condenser.

You’ll need a screwdriver to loosen the screws. Once opened, you can easily identify the run capacitor which looks like a battery (canister-like shape) but is bigger. It has three terminals on top and attached to the colored wires from the AC unit. Don’t touch the capacitor until it is discharged.

Take a picture of the capacitor paying attention to the colored wires and their specification. You’ll need this later as well as when you purchase a new capacitor. Make sure the replacement capacitor has the same voltage rating. You can ask the store to guide you on the proper capacitor.

4.      Discharge the capacitor.

Using a well-insulated screwdriver touch the metal end across the two terminals of the capacitor. This will discharge all remaining energy for safe removal and handling.

5.      Disconnect the old capacitor and replace it with the new one.

Remove the capacitor from its holder and disconnect all wires. Bring out the new capacitor and connect wires at their respective places. Alternatively, you can disconnect the wires at a time then fit each one back into their designated places on the new capacitor.

Test all the connections, ensuring that all wires are tightly connected at their respective terminals. After all the wires are connected, mount the capacitor in place.

6.      Check the condenser.

Switch on the breaker. Turn on the AC unit and adjust the thermostat. If the condenser runs normally, then you’ve done a great job. Simply put back in place the access cover and the unit is ready!

Finally, while it’s possible to DIY replace an AC capacitor, always think safety first. If you are unsure or worried about how to proceed, please call a certified AC technician.  These professionals will not only replace the capacitor, but they can also help diagnose other unexpected problems and provide you with expert tips on how to avoid similar issues.

Thanks For Reading 
More Read On Forbes Magazine 


Please enter your comment!
Please enter your name here