How To Reduce Noise From An Outside Air Conditioner: 7 Easy Ways

Written by Michael Harris
Last updated

Anyone who has ever lived next to a window air conditioner knows the feeling of being jolted awake by the sound of the compressor kicking on in the middle of the night.

Or maybe you’re tossing and turning, trying to get to sleep on a hot summer night, only to be kept awake by the steady hum of the AC unit.

Either way, it can be tough to get a good night’s sleep when you’re living with a noisy air conditioner.

Thankfully, there are a few easy ways to reduce the noise coming from an outside air conditioner and in this post, we’re going to walk you through them. Let’s get started.

what causes a noisy air conditioner?

An air conditioner is a complicated machine with many moving parts which interact with each other. So there can be many reasons why your air conditioner is loud such as:

  • Dirty blade fan
  • Insufficient lubricant
  • Loose AC duct
  • Leaking freon
  • Improper fitting in the wall
  • Old and rusted components

Old or faulty air conditioners can create enough noise to annoy yourself and your neighbours, disrupt the peace of your space and may even cause a headache.

If the humming, vibrating and tap-tap from your air conditioner disturbs your sleep or your peace during the day, these are the things you can do to minimize the noise:

1. Use Noise Reduction blanket

To soundproof something, you should add a blocking layer between it and the environment around it. So you can consider a dense material that can cover your AC unit which has noise-reducing properties.

Acoustic blankets are a good way to soundproof a noisy air conditioner. They have the added benefit of increasing air circulation.

A good sound blanket will have loops and hooks to easily attach itself to the unit and should reduce noise by 30-40%. They come in a 1 or 2 piece design depending on the brand of the compressor. A 2-piece blanket is a good idea when the compressor is close to the coil or the fan.

2. Install a Fence

A fence surrounding the air conditioner can do the job. You should also consider the material and placement before building.

You wouldn’t want to have an A/C between two walls as the sound would just amplify and get worse.

I would recommend installing a bamboo pole fence higher than the air conditioner placed at a distance of 1-2 feet away.

A more sustainable idea would be to plant shrubbery or trees around the AC unit as this would do the job of a noise-reducer and provide a sort of green-belt. Plant some bushes and shrubs around your air conditioner, you will achieve a soundproofing effect.

Place the fence at a distance of at least 1-2 ft from your unit to be able to effectively decrease the noise. These distances are somewhat better because the noise isn’t hitting the fence directly.

3. Choose The Best Suitable Surface For Your AC

If the cause of the noise is the unsteady contact with the ground or wall, then changing the surface or repositioning it can help.

For example, you can add foam beneath the air conditioner to reduce the vibrations. For this purpose, you can use some kind of foam to fix it.

Once positioned properly, your air conditioner will not produce any unpleasant vibrating noise. Of course, if you find some other type of noise present, this step won’t help you.

4. Fix The Water Dripping Noises

In many cases, it is not the unit but for the water dripping from your unit causing the noise issue. And you might not want to keep your windows closed all the time, especially during the summer, to enjoy the fresh air.

The solution to this is quite simple as all you need is a hose and a bottle. Fix the hose to the air conditioner’s hose and direct the other end into the plastic bottle.

5. Pick The Right Location For Your AC

If you have no choice but to buy a noisy air conditioner, you can prepare for it by choosing the right position for the AC before installing it.

Place it further back of your house or apartment. of course, you will need to balance between your own bedrooms, living room, dining room, and the neighbors’ household as well.

By doubling the distance between you and your air conditioning unit, you can reduce the noise by 6dB.

Try to avoid installing the unit between walls or corners with reflective surfaces. This is because sound waves can reflect off any obstructive surfaces and amplify, thus worsening the noise problem.

6. Schedule Regular Air Conditioner Maintenance

Noise can also be caused by debris stuck inside the unit, damage to components or old components. Getting regular maintenance, especially if you use the unit heavily, can prevent and fix such issues.

A regular check includes checking the thermostat, tightening electric components, lubricating moving parts, changing air filters, cleaning condensation lines and checking system controls.

7. Troubleshoot the Air Conditioning Unit

If you are confident about your DIY abilities then check for the following and fix these using simple tools:

  1. Check Fan blades: The blade fan is made of metal and if bent, they can hit other components inside the unit. Upon inspection, if you find that the blades bent or curved, you need to replace the blades or properly align it to overcome the problem.
  2. Check for foreign objects: Most air conditioners are outside the window and this allows animals, debris and dirt to enter the unit. If this happens, switching off the air conditioner as soon as possible and open the front.
  3. Switch it off and remove the objects and fasten the grills. Lubrication: If the air conditioning unit has oil ports, you may notice the lubrication wearing away with time. You will need to lubricate it by adding a couple of drops of SAE 10 oil to the motor.
  4. Clean Dirty Coils: Dust, dirt and small objects can collect around the coil fins, causing the unit to make excessive noise. You have to remove that dirt using a brush attachment on your vacuum cleaner or cloth.

Final Thoughts

All these suggestions are relatively inexpensive compared to the option of just buying a new unit. These small fixes can add more comfort to your life at a small cost.

Let me know if you have other tips to reduce noise from an air conditioner, or check out my other articles about quiet products and soundproofing.

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About The Author

Hey I'm Michael and I run this website. I'm a professional voiceover artist and in my search to create a silent studio I've become obsessed with soundproofing and things being quiet. Thanks for visiting and if you have any question get in touch.