What Is an HVAC Capacitor?

If you own or manage a business property in Phoenix, your air conditioning system works hard virtually all year. The HVAC capacitor is a little but important part that keeps it working smoothly. Read on to learn more..

An HVAC capacitor is an electrical part that stores and releases energy to assist motors start and run smoothly. Capacitors are very important for powering important parts of commercial air conditioning systems, like the blower motor, condenser fan motor, and compressor motor.

What Does an HVAC Capacitor Do?

Capacitors give the system a burst of electricity when it starts up and assist keep the electrical current stable while it runs. Motors have trouble turning over and can overheat or break down without this boost.

There are two primary kinds of capacitors for HVAC systems:

Start capacitors

These provide motors a big boost of power to help them start up quickly. They stop working when the motor reaches its operating speed.

Run capacitors

These keep the motor running smoothly and efficiently by providing a steady flow of energy while it is running.

Many commercial systems have dual run capacitors, which let the compressor and fan motor work together in one unit.

How to Tell if Your HVAC Capacitor Is Failing

Capacitors wear down over time, especially in Phoenix, where the weather is very hot. Some common warning indicators are:

• The AC unit has trouble starting or won’t start at all
• Warm air blowing from vents
• Strange humming or buzzing sounds • Fans not spinning or running all the time
• The system shuts down often
• The energy bills go up even when usage stays the same

Ignoring these signs can hurt the motor, which is much more expensive than replacing a capacitor.

Should a Capacitor Be Replaced Immediately?

Yes. A bad capacitor puts stress on motors and other electrical parts. If you keep using the system, it might trigger a chain reaction of failures, including damage to the compressor, which is one of the most expensive HVAC repairs.