Solved! Why Is My AC Unit Fan Not Spinning?

Keeping cool when it’s hot outside requires a properly working AC unit. If your AC unit fan isn’t spinning, here are some ways to troubleshoot this common issue.
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AC Unit Fan Not Spinning

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Q: Help! It’s hot in my house, and the AC unit is running, but it isn’t blowing cool air. Why is my AC unit fan not spinning? Do I need to call a professional, or is this something I can fix myself?

A: If there are problems with the AC unit fan not spinning, the air conditioning unit will not keep a home cool. There are a few reasons why the fan would stop working even though the unit itself is running. Some of the solutions can be as easy as checking the circuit breaker or changing the filter, while others will require a professional to diagnose and fix the problem. In the meantime, check out some alternative ways to keep your house cool when your AC unit isn’t working.

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The circuit breaker has been tripped because of overheating.

AC Unit Fan Not Spinning Check the Circuit Breaker

If the AC unit fan is not spinning, the first thing to check is the circuit breaker. Take a look at the circuit breaker associated with the AC unit and see if it’s been tripped. A circuit breaker may trip from overheating due to outside temperatures and the motor’s heat. If this is the case, flip the switch at the electrical panel and see if that solves the problem. Some AC units may have a shutoff on the unit’s side; double-check that it hasn’t been switched off too.

The capacitor might be defective, and you might need to replace it.

A capacitor is a small cylindrical component that stores energy and powers the air conditioner’s fans. AC units have more than one capacitor, including the start capacitor, which starts the motor, and a run capacitor that keeps the motor running. If a capacitor is old and weak, it can cause the fans to stop spinning. If a capacitor is defective, it will need to be replaced by an HVAC professional. Delaying replacement could cause the motor to burn out and lead to more expensive repairs.

AC Unit Fan Not Spinning Fan Motor is Burned

The fan motor is burned out and needs to be replaced.

The fan motor is the workhorse of an AC unit. It can burn out when it’s overworked and not routinely maintained. Depending on the air conditioning unit’s age, an HVAC professional might suggest replacing the entire AC unit since fan motor replacement is costly.

The air filter might be clogged, and you need to clean or change it.

Another cause of an AC unit fan not spinning is a clogged air filter. If you can’t remember the last time you replaced the unit’s filter, it’s time for a replacement. This is an approachable solution for homeowners to tackle. Air filters can get clogged with dirt, dust, fur, pollen, and other debris. If the air filter is clogged or blocked, airflow will be restricted, which can cause ice buildup. If ice is around the evaporator coil, the fan could stop working and cause the coil to freeze. Sometimes replacing the air filter will solve the problem, but if the coil is frozen, it’s recommended to call a professional.

A faulty belt might need to be replaced.

Over time, belts can become brittle and weak. It’s common in belt-powered AC units for the belts to be replaced when they cause a fan to stop spinning. An HVAC professional can easily replace old, worn, or loose belts.