How to Fix a Noisy Air Conditioner

Follow these steps to make sure your AC unit is in good working order this summer.

AJ Dellinger Contributor
AJ Dellinger is a contributor to CNET.
AJ Dellinger
4 min read

Hot weather is here for many parts of the US. Is your air conditioner ready?

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It's summer time, it's starting to get hotter out each day and we're all relying on our air conditioners to keep cool as the sun beats down on us. There is nothing worse in that situation than the loud clunk or constant churning of the AC.

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Sometimes air conditioners are just loud and sometimes those sounds are warnings of bigger problems that need to be addressed. When your air conditioner starts to act up, the last thing that you want to do is just wait it out and end up with a non-functioning AC unit in the heat of the summer.

When your air conditioner starts to make noise, don't worry: there are some fixes you can try right now to get it running smoothly again. If these tips don't work, it might be time to call in an expert.

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Identify the noise

The first step to fixing your noisy air conditioner is figuring out what the noise is, exactly. Knowing what sound the air conditioner is making can help point you in the right direction as to what's wrong and what the solution might be. 

Banging noise

One of the most common sounds you might hear coming from your air conditioner is a banging noise, as if parts inside the machine might be loose. This may often be accompanied by a rattling. It could be a number of issues, including a loose part within the air conditioner's compressor, which use refrigerant to cool down hot air.

Clanking noise

Clanking noises, similar to banging noises, may be a sign of loose parts that need addressing. However, it could also be related to the fan blades. Sometimes fan blades become loose or lose their balance and can do damage to other internal parts of the machine.

Buzzing noise

If you hear a constant or consistent buzzing coming from your air conditioner, there are a number of potential issues. These range from a problem with the fan motor to an electrical issue with the compressor to loosened or damaged isolation feet that otherwise prevent vibrations and shaking from occurring.

Squealing noise

Of all the sounds your air conditioner might make, a squealing noise may be the most troubling indicator. This may mean that your air conditioning unit is having internal pressure issues that could become dangerous. It may not be that serious -- it could be a loose belt, for instance -- but it's one that requires addressing quickly if you hear it.

Address common air conditioning issues

While some air conditioning issues are more serious than others, all deserve to be addressed in order to ensure that your air conditioning unit is working properly and keeping you safe as well as cool. Before you get started, make sure your air conditioner is turned off and unplugged -- and follow any other safety precautions specific to your unit. 

Clear debris

One of the most common causes of a noisy air conditioner is simply a collection of dust, dirt, and debris inside the machine. This happens from standard use. Clear out anything that shouldn't be there or might be getting caught in the fan or other parts of the machine and see if that helps clear up some of the noise.

Tighten screws

Another common issue that can lead to a noisy air conditioner is the loosening of screws and other parts. This comes from normal use and wear and tear, and the machine will inevitably end up with loose parts -- particularly screws and other other supports. Try tightening them up and determining if that helps the machine run quieter.

Clean coil fins

Coil fins are the part of your air conditioner that helps facilitate the heat exchange process by evaporating the heat from the air as it passes through the system. Sometimes these coils can get bent out of place, which can both slow airflow and result in a noisy air conditioner.


To keep things running smoothly, sometimes you need to lubricate your air conditioner. Check the motor and any belts that may be the cause of excess noise and apply a lubricant in order to make sure everything is running smoothly.

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When to call an expert

If any of these sounds persist after trying the more common solutions, it is worth calling in an expert to take a look. When problems occur with air conditioners, they are worth fixing immediately if possible, especially if they may be a signal of a much bigger issue that might be around the corner if the problem isn't addressed.

As the summers get hotter, having a working air conditioner is more vital than ever before. It's a key to health when the temperatures rise to extreme levels, and it helps to keep your home comfortable and livable. For that reason, it's worth doing regular cleanings and repairs to your air conditioner when possible to make sure it is running as smoothly as possible. If it starts getting noisy, check out what the cause is and try to address it -- and don't be afraid to call an expert to make sure your air conditioner is available and working when you need it most.

Check out some of our other tips to keep your air conditioner in good condition: