The fan motor is a critical component of your air conditioning unit. If this part fails, your AC won't be able to move cold air through your home or hot air out of it. There are several reasons why a fan motor may stop working. Here are a couple of those reasons and tips on diagnosing the problem.

Capacitor Problems

One of the most common reasons a fan motor may suddenly stop working is if the capacitor goes bad. Capacitors are like batteries. They store a small amount of energy and use that energy to jump start the fan motor and help keep it running. If the capacitor goes bad, the fan motor won't turn or stay on.

There are a variety of reasons these parts stop working. Sometimes the capacitor just wears out over time and becomes unable to hold a charge. Other times, surges in the electricity can damage the part. You can usually tell when the capacitor is starting to go out when you begin hearing a clicking sound.

An easy way to determine if the fan isn't working because of the capacitor is to use a thin stick to gently push one of the fan blades. If the fan starts spinning on its own, then the problem is likely the capacitor. Another way to confirm the issue is to listen for the condenser. If the condenser is running but the fan isn't, then the capacitor is causing your trouble.

Contactor Issues

The contactor helps regulate the flow of electricity to the fan motor and the compressor. When the contactor goes bad, it may start sticking and the respective motors won't turn on or off properly. A bad contactor doesn't just cause your fan motor to malfunction; it can also damage your compressor. If the switch fails to turn the compressor off at the appropriate time, the compressor will continue to run until it dies. Since it can cost up to $1,053 to replace a compressor, you'll definitely want to fix a broken contactor as soon as possible.

There are a couple of ways you can determine if the reason why the fan motor isn't working is due to the contactor. The easy way is to turn the air conditioner on and listen. If neither the compressor nor the fan motor turns on, the problem is likely the contactor. You can also directly test the contactor using a multi-meter. If there is power entering the contactor but none coming out, then the part is bad.

Both of these issues are easy to repair. If you'd rather not fix the problem yourself or neither of these issues appears to be the problem, then contact a professional air conditioning repair company for assistance.