How To FIX AC Unit’s Fan Not Spinning [5 Common Issues]

Dominic Mitton
By Dominic  • Reviewed by Ben  • Updated:   October 26, 2023
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When a fan stops spinning, there could be tons of different reasons – from more serious ones to ones you can easily fix in a few minutes.

There’s no room for panic as it’s quite often an issue that almost every AC owner will have to deal with.

Let’s talk about the most common reasons why your air conditioner’s fan started spinning all of a sudden.

Most Common Reasons Why Your AC Unit Fan Isn’t Spinning

Broken Belt

After a long time of usage, belts usually become weak and they can’t function properly anymore.

They’re responsible for the fan’s functionality, and once they get faulty – the fans won’t spin how they are supposed to.

Replacement belts are usually not expensive and any HVAC technician can do it quickly for you.

Clogged Filters

Clogged air filters are one of the most common issues why your AC isn’t working properly, and it’s the same when it comes to fans not spinning.

Air filters often get clogged with dust and dirt which block the airflow. Also, it can cause ice build-up and potential water leaks.

Replacing air filters shouldn’t be an issue, but if your coil is frozen, you should check out how to unfreeze your AC instantly.

Motor Issues

If you haven’t maintained your unit’s motor and it has been overworking for a long time – it might be that the motor burnt out.

This is a serious issue and the motor isn’t the cheapest part – so you can expect this issue to be a bit pricey to replace. Furthermore, it might be possible that you need to replace the entire HVAC system.

It’s recommended to seek an HVAC technician for regular maintenance to avoid this issue.

Defective Capacitor

The capacitor is responsible for transmitting energy signals to power the motor of the whole unit.

Most AC units have several different capacitors, ranging from start capacitors to run capacitors.

Start capacitors send the power to the motor and run capacitor keeps the motor going.

Capacitors are one of the reasons why your AC starts and then stops quickly.


You should check the circuit breaker and see if it has tripped.

Circuit breakers can usually trip from overheating because the motor is working too hard to deliver the desired temperature.

If this is an issue, you just have to flip the switch and it should start working normally again.

Tips to Prevent Your AC Fan From Breaking Down

Regular maintenance – You should consult an HVAC technician to maintain your unit every 6 months, the best would be before the summer as air conditioners tend to work the “hardest” in that period.

Clean your filters – You would be surprised at how filters can quickly get clogged with dirt and debris, so make sure to clean them once a month.

Don’t overwhelm your unit – When the summer heat starts blasting, it’s expected that your unit will be a bit overwhelmed. Try to not keep it running for too many hours a day, especially during the night or when you’re not at home.

Hey there! I am Benas, the founder and content editor at Home Caprice. Thanks for reading the article. I hope you were able to find what you were looking for. I and my team are here to simplify heating and cooling for everyone. Please have a look at the About page for more details about our website and feel free to check out our editorial process.