How to Reduce The Sound From My Air Conditioner Unit

Caution: Before making any modifications or taking on any maintenance tasks remember to take these steps.

Important to know about noisy air conditioners

Newer air conditioner models are always quieter than older versions due to new technology being manufactured.
If the noise is coming from the compressor, then you will need to replace it because it has worn out.
Your air conditioner could have dirty fans from gathering a lot of dust. Try giving your air conditioner’s fan a good cleaning and see if that helps with the noise.
Depending on the age of your air conditioner, repairs or modifications might not help with the noise. Replacing the unit with a newer and quieter model will be more beneficial for your home. A 10-year-old air conditioner is an example of being too old for repairs.

Fencing: Try putting a fence in front of or around the air conditioner, this creates a barrier for the sound and traps the sound’s movement. You can use plywood to fence the air conditioner, or buy an air conditioner fence. Remember to keep the fence at least 3 feet away from the air conditioner to allow proper air flow. For the best noise reduction, try leaving no gaps in between the fence boards. You can reduce gaps by overlapping the fence boards.
Use a Sound Blanket: Your manufacturer will have the information on what sound blanket fits your unit. You can also purchase a universal sound blanket online.

Strategically place your air conditioner away from everyday living spaces like bedroom windows, living rooms, or patios. The farther you are away from your air conditioner, the less sound you will hear
Do not place your air conditioner between brick walls or multiple reflective surfaces this can cause an echoing effect and amplify the noise.
You can try to enclose the air conditioner like with the fencing method, but be aware that performance can be inhibited if it restricts airflow
Air conditioners are going to be noisy, the cheaper the air conditioner, the more noise it will most likely make. Manufacturers construct premium air conditioners with reduced noise for this purpose. If you cannot stand the sound of your current air conditioner and have taken the steps to reduce the noise but are still not satisfied, then consider buying a higher model that is built to be quieter and more efficient.

The below areas are taken from soundproofing.org

Window Units

If you removed the front vent panel and filter, you would be able to see the other side of the air conditioner. What does this mean? It means noise from the outside has a free path to reach the inside of your home. The solution to outside noise coming in through your window unit is to build a shield to block the incoming sound. You can get a fitted to prevent this opening to reduce the noise significantly.

Outside Units

Most of the time these units are large due to the heavy workload we demand from them. Outside A/C units tend to do more than just cooling; they sometimes heat also. So to reduce the noise of that is usually produced from the compressor your have to build a fence around it.

Attic Units

It is necessary to add a sound barrier and vibration absorbing mat around the installation to reduce sound transfer into the building. Request this to be done during the initial installation.

Air Vents

Ducting needs to be covered with closed cell sound absorbing foam, for sound and thermal insulation.
Metal ducting needs to be physically isolated from the fan shroud or air-con unit with a flexible coupling. Otherwise, is will re-radiate sound vibration along its length.
Fiberglass or flexible ducting usually won’t have this problem, but will lose thermally if not insulated.