What Is an Air Conditioner Capacitor? Exploring the Key to Keeping You Cool

No one wants to blow a fuse every time they run their AC, and you can thank your air conditioner capacitor for ensuring that doesn’t happen. So, what is an air conditioner capacitor? This small but essential powerhouse of an HVAC system keeps your system running smoothly without running up the electricity bill. Let’s see how it manages such a praiseworthy feat.  

What Is an Air Conditioner Capacitor? 

The air conditioner capacitor is an integral part of how an AC works. The capacitor is basically the battery of an HVAC system. It’s a small cylinder in the air conditioner that stores energy and kick-starts the motor in the unit, helping cool things down faster. 

While a home’s electrical system powers most HVAC processes, your system needs a serious energy boost to start cooling down your home. That’s why the capacitor stores energy, providing that big surge to get the motor moving.

A malfunctioning or broken AC capacitor won’t immediately break your HVAC system, but it will lead to higher energy bills and quickly wear down the motor. Once an AC capacitor wears out, you’ll notice your AC won’t cool down your home efficiently, which can lead to additional problems with the air conditioner.  

Types of Air Conditioner Capacitors

Depending on the type of air conditioner you have, your system may have a single capacitor or two capacitors.

• In systems with two AC capacitors, the start capacitor delivers the energy to the AC to get the motor started, and that’s it.   

• The run capacitor takes over once the start capacitor gets the AC going. This capacitor keeps the system going, storing energy and releasing it to keep the motor spinning. 

• Some HVAC systems will have a dual capacitor, which performs the job of the start and run capacitor in one. 

Older HVAC systems tend to have two capacitors, while newer models combine their functions into a single dual capacitor. If you need to replace an AC capacitor, your local HVAC repair company may opt to replace the two capacitors with a single dual capacitor, making it easier for your AC to run and stay healthy for longer. 

Common Causes of AC Capacitor Failure

From time to time, parts of your HVAC unit may fail, and air conditioner capacitors are no exception. Check out the most common causes of failure, and see how you can work to ensure your capacitor has the longest life span possible.

Overheating

If your outdoor AC unit is in an area that gets constant sunlight, it’s likely to fail quicker than one that’s in the shade. Install an awning over your outdoor unit to give it some shade during the hotter months. Additionally, turn the temperature up during summer. Trying to cool your home to 65 degrees Fahrenheit when it’s 99 degrees outside is a recipe for AC capacitor disaster. 

Power Surges

A power surge can damage the AC capacitor in your home. There are many reasons power surges may happen, not all of which are preventable, like lightning strikes. However, calling an electrician to inspect and possibly upgrade the amp capacity of your home can help prevent surges from things like large appliances turning on and off. 

Worn or Damaged Parts

HVAC maintenance is crucial for the health of your entire unit. If one part of the system is down or damaged, it can negatively impact every other component of the unit. Consider investing in an HVAC maintenance plan so that the pros can catch any small issues before they become big ones.

Age

Air conditioner capacitors have an average life span of 20 years as long as they stay in good shape. If your capacitor is getting close to that 20-year mark, it may fail as a part of its natural life cycle. At this point, you can thank the capacitor for its years of service and start shopping for a new one. 

Replacing an Air Conditioner Capacitor

A bad AC capacitor doesn’t spell doom for your entire AC system as long as you get it replaced as soon as you notice something’s wrong. And luckily, an AC capacitor can be replaced at a fraction of the cost of replacing an entire AC system. For most people, the cost to replace an AC capacitor averages $180, and it only takes a pro one or two hours to do. 

Before you consider replacing your air conditioner, call in a pro to confirm it isn’t just a broken AC capacitor slowing things down. If you suspect your AC capacitor has an issue, an HVAC technician can quickly test it. Because the AC capacitor deals with high-voltage energy, think twice before trying to test it or replace it yourself.