Why did my AC Capacitor Fail?
TechXpert verified by Ken Kontra
Your AC capacitor could be failing due to old age, overuse and overheating, or because of a constant variation in voltage. The AC capacitor and fan motor of your HVAC system go hand-in-hand; the former provides the latter with the electrical power it needs to function. Capacitors can be dangerous to handle, so it’s important to be careful when investigating the cause of your capacitor failure.
A Capacitor's Capabilities
The purpose of a capacitor is to provide energy for the motor of your AC system so it can circulate cool air into your home. Essentially, it gives the boost your system needs to start and continues to provide power for as long as the system is on.
Capacitors operate in short cycles. If your capacitor runs for a long period of time, it could overheat and burn out. As a result, it won’t be able to provide the energy needed to start your AC system.
Voltage variation can cause problems in hot climates and during peak summer times, when power companies can raise and lower the level of voltage delivered to your house. A higher voltage can make the chemicals inside your capacitor boil, causing it to swell. This swelling is a signal that it’s time to repair or replace your capacitor.
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