What is a Good Noise Level for an Air Conditioner?

Noisy air conditioners make life difficult. People want a quiet air conditioner but they have no idea what decibel (dB) they should look for. So, what is a good noise level for an air conditioner?

A good noise level for an air conditioner is below 40 dB because it does not affect our sleep and health. An air conditioner starts to disturb our sleep when its noise level at above 40 dB. Most people are highly-annoyed and sleep-disturbed when the noise level of an air conditioner is above 55 dB.

Unfortunately, not every air conditioner is as quiet as below 40 dB. Certain types of air conditioners are inevitably noisy due to the nature of their build.

If you want to have an idea of how quiet is 40 dB now, jump to the sound test video in this post which I’ll show you later in this post though.

How Loud is Too Loud for an Air Conditioner?

If you’re looking to buy a new air conditioner for your home, you definitely want to try to avoid air conditioners that create more than a 40 dB noise level.

Based on the research by the World Health Organization (WHO), I quote the following for your reference:

“Below the level of 30 dB, no effects on sleep are observed except for a slight increase in the frequency of body movements during sleep due to night noise. There is no sufficient evidence that the biological effects observed at the level below 40 dB are harmful to health. However, adverse health effects are observed at the level above 40 dB such as self-reported sleep disturbance, environmental insomnia, and increased use of somnifacient drugs and sedatives. Therefore, 40 dB is equivalent to the lowest observed adverse effect level (LOAEL) for night noise. Above 55 dB the cardiovascular effects become the major public health concern, which are likely to be less dependent on the nature of the noise.”

World Health Organization (Europe) Night Noise Guidelines for Europe

Hence, air conditioners that create a noise level above 55 dB are considered too loud. However, some air conditioners only produce 55 dB when operating at high fan speed. So, their noise level may be acceptable when operating at low fan speed.

There are a few common noise levels produced by an air conditioner. Following is my comment on the noise level:

Some air conditioners produce a louder noise than other air conditioners. So, let’s take a look at the common types of air conditioners and see how loud they really are.

Portable Air Conditioner

Portable air conditioners are known to be noisy. On average, most portable air conditioners with a cooling capacity of just 6000 BTU produce a noise level of around 52 dB.

The higher the cooling capacity, the greater the noise level.

At 12000 BTU, many portable air conditioners will create a noise level of around 56 dB which is considered too loud, especially for the bedroom.

Even when operating at the lowest fan speed setting, many portable air conditioners still struggle to keep their noise level below 50 dB.

Nowadays, portable air conditioners are making less and less noise. However, they are still not a good option if you want a quiet air conditioner.

Window Air Conditioner

Window air conditioners are more or less the same as portable air conditioners when it comes to quietness. However, some window air conditioners are significantly quieter than the quietest portable air conditioners.

On average, most window air conditioners with a cooling capacity of 6000 BTU produce a noise level of around 53 dB. At 12000 BTU, many window air conditioners also produce a noise level of 56 dB.

Window air conditioners can go up to 25000 BTU in cooling capacity. At such a high capacity level, they generate a staggering 60 dB of noise level which is unbearable to many people.

Fortunately, there are quite a number of good window air conditioners out in the market that have a noise level below 50 dB which makes window air conditioners better than portable air conditioners when competing for the quietest operation.

Ductless Mini Split Air Conditioner

Ductless mini split air conditioners blow away both portable air conditioners and window air conditioners in terms of quiet operation. They are best known for their incredibly quiet operation.

Still, if we compare some of the noisiest ductless mini split air conditioners, we are looking at a noise level of around 50 dB and that is for the highest cooling capacity model which is 24000 BTU.

At 9000 BTU, most ductless mini split air conditioners produce a noise level of around 42 dB when operating at the highest fan speed setting.

However, the above is only applicable to the indoor unit. How about the outdoor unit of ductless mini split air conditioners?

The outdoor unit of most ductless mini split air conditioners at 9000 BTU and 24000 BTU produces a noise level of around 45 dB and 55 dB.

Although the outdoor unit by itself is noisy, it is often installed a few feet away from the room. Hence, the real audible noise level is actually lower.

What is a Quiet Noise Level for an Air Conditioner?

Nowadays, many air conditioners are designed to be quiet. Manufacturers use methods such as super low fan speed mode and quiet mode to reduce the noise level generated by their air conditioners.

A quiet noise level for an air conditioner is below 40 dB. Still, some air conditioners struggle to keep their noise level below that to prevent sleep disturbance.

Portable Air Conditioner

Although most portable air conditioners are noisy, there are a handful of new portable air conditioners that are acceptably quiet.

Take the Midea Duo 12000 BTU Inverter Portable Air Conditioner (click to view on Amazon) as an example. It can go down to a noise level of around 42 dB which is significantly better than most portable air conditioners out there.

Here are a few comments about its noise level:

“The noise level is no issue at all. I work from home in my room and clients never even mention background noise from it.”

Meagan Darling

“The noise level is low enough to watch TV and have a normal conversation.”

Elizabeth A. Marker

“The noise level doesn’t bother me but if you have to have complete silence to sleep with it then you need something else.”

Susan G.

Midea has been rolling out quiet portable air conditioners for a few years. This is their latest best portable air conditioner. Although its noise level doesn’t go below 40 dB, it is pretty close.

If the Midea Duo is not your cup of tea, the second option will be the LG 14000 BTU Smart Dual Inverter Portable Air Conditioner (click to view on Amazon). Its lowest noise level is slightly higher at 44 dB.

Many people who bought it find it quiet enough for a good sleep.

I don’t think there is another portable air conditioner that can beat the above two when it comes to low noise operation based on what I’ve seen so far.

So, if you need a portable air conditioner that is quiet, the above two portable air conditioners that I mentioned are worth considering.

Window Air Conditioner

Window air conditioners generally have more options than portable air conditioners when it comes to low noise levels. However, they also struggle to go below 40 dB.

On my radar, the all-time best window air conditioner that is also quiet is the Midea U-Shaped 8000 BTU Inverter Window Air Conditioner (click to view on Amazon). At the lowest fan speed setting, it generates a noise level of 42 dB.

Here are some of the comments about its noise:

“It’s super quiet, and it cools my bedroom down very quickly. Bravo, Midea!”

Amazon Customer

“I am on remote calls all day due to the pandemic and really needed something quiet that could keep me cool during super humid heat waves. This unit won hands down.”

K. D’Anna

“Build quality is good, and unit is extremely quiet, because of the design with the noisy part outside the partly closed window.”

rABAB WARD

This window air conditioner is smart because it puts the noisy compressor outside the window which further reduces its overall noise level.

For the second option, I would say is the Frigidaire Gallery 8000 BTU Inverter Window Air Conditioner (click to view on Amazon) that produces only 41 dB at the lowest fan speed setting.

However, this Frigidaire unit does not have the design like the Midea unit. So, outside noise may contribute to the overall noise you’ll be hearing in the room.

Again, there is no other window air conditioner that has the same standard come close to the noise level offered by the above two.

So, if you’re looking for a quiet window air conditioner, the above two window air conditioners that I mentioned are worth considering.

Ductless Mini Split Air Conditioner

Ductless mini split air conditioners can easily go below 40 dB. In fact, most 9000 BTU ductless mini split air conditioners only produce a noise level of around 25 dB when operating in low fan speed mode.

Many ductless mini split air conditioners offer a quiet mode which further brings their noise level down to around 21 dB. At 21 dB, I barely can hear any noise coming out of my bedroom air conditioner.

Out of curiosity, I did a casual sound test for my bedroom ductless mini split air conditioner and below is the recorded video. You can listen to different noise levels at different fan speeds.

I start the sound test by recording the noise in my room before turning on the air conditioner as a benchmark. Then, I turn on my air conditioner and it automatically starts with the highest fan speed and immediately goes back to the previous fan speed setting that I had which is on quiet mode.

On quiet mode, I barely can hear any noise coming out of my bedroom air conditioner. The official sound level stated by the manufacturer (Daikin) is 22 dB. I like to have it on quiet mode most of the time so that I can concentrate on my writing.

Then, I change it to low fan speed and I still barely can hear any noise coming out of my bedroom air conditioner but it is definitely slightly noisier than before. The official sound level stated by the manufacturer is 30 dB.

I proceed to the medium fan speed setting and then, the highest fan speed setting. At the highest fan speed, the official sound level stated by the manufacturer is 41 dB. I never sleep with the highest fan speed setting because 1) it is noisy and 2) it is too cold.

Almost all ductless mini split air conditioners are as quiet as my bedroom one. They are quiet by nature because their physical dimension is bigger. Hence, air velocity is lower, air friction is lower and therefore, the noise level is also lower.

If you are interested in buying a ductless mini split air conditioner, I would recommend the Daikin Atmosphera R32 Inverter Ductless Mini Split Air Conditioner (click to view on Daikin Comfort). It is a new model and thus, it might not be available in some places.

Alternatively, I also think the Daikin 19 SEER Inverter Ductless Mini Split Air Conditioner (click to view on Amazon) is good and quiet as well.

So, if you are looking for the quietest possible air conditioner for your home, ductless mini split air conditioners are your best choice.

Conclusion

The loudness and quietness of an air conditioner are subjective. Different people have different tolerances against noise. However, most people feel good when an air conditioner kept its noise level below 40 dB. Furthermore, noise level below 40 dB doesn’t disturb our sleep and affect our health.

Ductless mini split air conditioners have the lowest noise level among other room air conditioners mainly portable air conditioners and window air conditioners. The lowest possible noise level produces by a ductless mini split air conditioner is around 21 dB.

Nonetheless, many portable air conditioners and window air conditioners have a low noise level approaching 40 dB which makes them considerable.