What should we do when the outdoor unit of the air conditioner is noisy?

Do you think the outdoor unit of your air conditioner is noisy?
The sound of the unit outside seems to be quite loud even though the windows are closed.

It can still be good if you live far from the house next door, but in condominium and apartment, you are also worried about the inconvenience of the surroundings.
So, now I will present the way to eliminate the noise of the outside unit.

What causes the outdoor unit to be noisy?

If the sound of the outside unit is noisy, you will often think that it is an error.
But the monstrous sound is not just due to the breakdown. The way the outdoor unit is installed and how dirty it is also depends on the noise level.
It is said that the sound of the outdoor unit is loud, but I will explain which part is called the outdoor unit.

What is an outdoor unit?

The external unit is placed outside the house and is connected to the indoor unit inside.
Inside the air conditioner, the refrigerant carries “heat” while heating and cooling. Refrigerant becomes liquid when compressed with gas at room temperature.
It exchanges heat with air by becoming gas or liquid.

During heating, the refrigerant is compressed by the compressor of the outdoor unit and changes from liquid to high-temperature, high-pressure gas. At this point, the refrigerant draws heat from the surroundings. The air that has been deprived of heat is emitted from the outdoor unit. The gas compressed by the compressor and raised in temperature flows into the indoor unit, turns into warm air and is supplied indoors.

When cold air is supplied, the exact opposite of hot air supply occurs. Refrigerant is deprived of heat and turns from gas to liquid and the deprived heat is emitted outwards from the outdoor unit. Refrigerant deprived of heat evaporates in the indoor unit and turns into cold air, which is then supplied indoors.

As mentioned above, outdoor units use refrigerant for heat exchange. The greater the difference between the indoor and outdoor temperatures during heat exchange, the greater the load on air conditioning processing and the louder the operating noise.

The reason for the noise in the outdoor unit?

The Outdoor units are not firmly fixed.

When the outdoor unit works, it vibrates, so if it is not firmly fixed to the base, it will make a noise.

The outdoor unit is dirty.

If the indoor unit is dirty, the activity of the parts will slow down and it will be difficult to get air out. As a result, operating efficiency is reduced and additional power will be used.
The operating noise may be louder when using extra power.

Outdoor units deteriorate over time.

The most common cause of abnormal noise in outdoor units is deterioration over time.
Running in different parts used for many years. Due to degradation over time, it may not work properly, or parts may not be properly involved and may sound abnormal.

How to get rid of unusual sounds?

Caused by the foundation.

Considering the noise, it is better if the foundation is strong, hard and heavy. If the foundation is heavy and stable, it will absorb the vibrations of the outdoor unit and reduce noise.
If the foundation is light and not as strong as plastic, you can reduce the noise by replacing it with stone blocks.

It is also effective to apply anti-vibration rubber between the outdoor unit and the base.
Anti-vibration rubber has a groove engraved on a plate-shaped rubber and the elasticity of this groove absorbs vibrations and reduces the noise caused by the shaking of the outdoor unit.

If caused by dirt.

If the cause is dirt, clean it.
As a result of this cleaning, you can expect to improve its operating efficiency and reduce noise. Clean it regularly so that dust does not accumulate and any foreign object does not get in contact with Zeno.

Caused by ageing deterioration

If it deteriorates over time, you may get injured or have an accident if you deal with it yourself, so please consider repairing or replacing it.
It is 10 years from the purchase as a guideline for replacement by purchase. After this period, it becomes impossible to order replacement parts and repair itself, or replacement by purchase becomes a more realistic choice.


There are various reasons for the noise.
If you do not know the cause, it can be dangerous to go it yourself. Ask a professional.

In Nagoya our company is engaged in the maintenance and repair of commercial air conditioners.
If the air conditioner does not work properly or you want to replace it, please feel free to contact us.





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