Keeping Your HVAC System In Great Condition

A Common Air Conditioning Repair: Replacing A Bad Capacitor

4 December 2020

Herbert Franklin

When your air conditioner stops working, it's difficult to know what went wrong. Even if your AC has symptoms of short cycling, blowing lukewarm air, or not blowing air at all, different things could be to blame. This is the case with capacitor problems.

The signs of a capacitor going bad are also signs of other problems, so your air conditioning repair person will have to diagnose the problem. Here's a look at the purpose of capacitors in your air conditioner and the repairs needed when a capacitor goes bad.

The Purpose Of AC Capacitors

Capacitors are electronic components that help power motors. When a motor turns on, it pulls more power than it uses when running continuously. The capacitor acts like a battery that supplies the initial boost of power to help a motor turn on. This type of capacitor is called the start capacitor.

Motors often have a second capacitor called the run capacitor that helps the motor run properly after it has kicked on. Your air conditioner may have three main motors, and each might have one or more capacitors. Without capacitors, your AC might not be able to turn on or keep running.

The Signs A Capacitor Is Bad

Your AC will put out air that isn't chilled or will produce low airflow when a capacitor is bad, but those could be symptoms of other problems too. One thing that can definitively signal a bad capacitor is a humming coming from the condenser.

Another sign is when you look inside and see the capacitor is leaking, bulging, or otherwise damaged. An air conditioning repair person can tell for sure a capacitor is bad by taking voltage readings with a meter.

The Repairs Needed For A Bad Capacitor

The only solution for a bad capacitor is to put in a new capacitor and get rid of the old one. Fortunately, a capacitor is a fairly inexpensive part, and replacing a capacitor is a common type of air conditioning repair.

Capacitors can go bad due to old age, and they can also go bad when they overheat during a hot spell in the summer. Once a capacitor is burned out or worn out, it can't be repaired. Instead, the repair technician will replace the part.

A capacitor looks similar to a battery, but it's a little more complicated than that. One thing to know is that a capacitor can hold on to a charge even when the power is off, so you don't want to attempt DIY repairs unless you know for sure what you're doing as you could get electrocuted. Another important step is to choose the right replacement part so your AC works properly. There are different kinds of capacitors, and you need one intended for the brand and model of your air conditioner.

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