Top 8 Quietest Wall AC Units for Different Room Sizes!

Loud AC units can be super annoying. A few of my readers have asked if I could provide some recommendations for quieter models.

For this purpose, I decided to test some supposedly quiet models and see which ones truly fit in that category. These are, without a doubt, the quietest ones that I could find that are also great overall in terms of price and quality.

Before sharing the reviews, I’m presenting you with some critical information that will help you understand wall AC units better. This should help you pick the right unit for your requirements. Alternatively, you can skip to the reviews section immediately if you’re in a bit of a hurry. 🙂

How Does a Wall Air Conditioner Run?

A wall AC operates by absorbing hot air in the room into the cooling unit. The absorbed hot air moves over the AC’s evaporator, the refrigerant absorbs the heat in the air, and the air gets cooled.

The cooled air is then released into the room. The absorbed heat in the condenser is expelled through the air conditioner’s vent to the outside. This prevents the room from heating up.

How to Install a Wall Air Conditioner

Listed below are the steps involved in installing a through-the-wall AC.

  1. Create a hole to house the AC in the wall.
  2. Installation of wall sleeves:

These are essential for housing the AC unit in the wall. It also helps in the ease of maintenance of the unit. There are two types of sleeves. First is the traditional sleeve type that only vents at the back and is compatible with different models of wall AC.

Second is the slide-out chassis sleeve that is specially built for a particular unit. It usually vents at the back and on the sides. Some brands of AC manufacturers offer products that are compatible with sleeves from other brands. This helps to make installation or replacement with another brand effortless.

  1. Install the AC.
  2. Plug into the nearest electric socket.
  3. Protect the exterior of the AC with weatherproof stripping.

Consider THIS Before Buying & Installing

There are some factors you have to put into consideration when buying a through-the-wall air conditioner. Some of them are:

1. Wall Thickness

As mentioned earlier, the back of the AC has a vent that expels heat to the outside. This, therefore, means that the wall that will be housing the AC has to be an exterior one. Also, the thickness of this wall is vital to let you know what AC type to buy.

2. Noise Level

Noise is damaging to the ear. There are two types of noise that cause significant damages. They are:

  1. A one-time exposure to a source of a high noise such as a shotgun fired near your ear.
  2. Long, continuous exposure to low-level noise such as in loud air conditioners.

The standard exposure time to reduce hearing loss risk based on exposure to about 70 and 85 decibels is between 8 and 10 hours.

Classic air conditioners have a rating of about 60 decibels, but through-the-wall air conditioners are a solution to air conditioning noise problems. They were designed for installation in places like hotel rooms, bedrooms, etc., making their ratings to be about 50 decibels or even lower in some cases, close to the sound of refrigerators.

3. The Right Room Size and AC Power

This point is crucial because it will help you get the right AC with a suitable capacity. If the room is bigger for the AC, it will not cool the space effectively. On the other hand, if the room is smaller than the AC, it will consume more electricity, cool the room quickly and make more noise going off and on.

BTU (British Thermal Unit) value gives us the unit of power of an AC. The general rule is that an AC needs about 20BTU per square foot. To measure the capacity for a room, you will multiply the length by the room’s width. For two rooms having no doors separating them, add up the results of their area.

S/N Area of space to be cooled (square feet) Air Conditioner Capacity (BTU) needed
1 100 – 150 5000
2 150 – 250 6000
3 250 – 300 7000
4 300 – 350 8000
5 350 – 400 9000
6 400 – 450 10000
7 450 – 550 12000
8 550 – 700 14000
9 700 – 1000 18000
10 1000 – 1200 21000
11 1200 – 1400 23000
12 1400 – 1500 24000
13 1500 – 2000 30000
14 2000 – 2500 34000

Other adjustments to be considered in this sizing according to are to:

  1. Reduce the capacity by 10 percent if you’re dealing with a heavily shaded room.
  2. Increase the capacity by 10 percent if dealing with a room with more access to direct sunshine.
  3. Add 600 BTU for every additional person in the room if more than two people stay in that space.
  4. Increase capacity by 4000BTU if the unit will be in a kitchen.


Generally, wall ACs have capacities ranging between 8,000 and 24,000BTUs. But the most common ones fall in the 8,000 and 14,000 BTUs ranges. Having established the most important aspects of wall AC units, I will be giving my reviews for eight of them under three main categories.

Note: The affiliate links below lead to the AC product pages on Amazon where you can check the current price, customer reviews and other current information.

Quietest ACs for Small Rooms (300-400 Square Feet)

Here are my top picks and their tested reviews for small-sized rooms such as the bedroom, study, office space, etc.

LG LT0816CER (56 decibels)

This AC ticked all the features I wanted in an air conditioner suited for a small room. It has both a cooling and heating system. The cooling and heating capacity is 8,000 BTU. I’ve used the air conditioner more, and so far, it’s done a great job. It cools the whole space efficiently.

Even though it is not completely as silent as the labeling suggests, it is quieter than the ones I’ve used before. The anti-corrosion gold-coated fin of this unit serves as a protective cover for its durability.

Koldfront WTC8001W

I’ll give it a 3 on a scale of one to ten for noise level, with ten being the highest noise level. It isn’t too bad at all for an 8,000 BTU capacity air conditioner. When using the heater, it is so quiet that a call or meeting can be held where it is installed. This means that in any room it is installed it won’t disturb regular conversations.

The fan speed settings are mightily helpful at reducing noise, though the performance will naturally be impacted also. Even though it has a heater, it didn’t heat the room as much as I wanted, thanks to its 4200BTU capacity.

Quietest ACs for Rooms of 400-450 Square Feet

For bigger room sizes, my top picks and their tested reviews are as follows:

LG LT1037HNR (noise level, 56db)

It is the costliest in this category, but I particularly love its shape. It adds a beautiful effect to the interior wall of the room. This unit has both high heating and cooling capacities of 10,000BTU and 11,200BTU, respectively.

You can comfortably hold conversations without distractions, and in its low fan levels, you can soundly sleep as well. One thing to bear in mind in installing it is that it has a different electrical outlet from the standard one.

Perfect Aire 4PATW10000

A great feature that this AC offers is the follow-me thermostat technology embedded into its remote control. The sensor in the remote control works with the body temperature and makes the cooling effect circulate more to where you are staying while in the room.

In addition to its quiet sound, like other ACs in its category, it has three fan speed levels, which help reduce noise when the fan is at work.

Koldfront WTC10001W

If you’re looking for a safe and eco-friendly product (considering the effects of some of these appliances on the ozone layer), you have found it. The refrigerant used in this AC is R-410A, known for not having Bromine or Chlorine in its constituent.

Knowing that a wall AC cannot be utterly silent since all the running parts are enclosed in one box, this AC still carries out its functions with minimal noise.  One of the disadvantages of this AC, which can be fixed during installation, is the electrical outlet. It is different from the standard one.

Quietest ACs for Rooms of 450-550 Square Feet

For room sizes of about 550 sq ft, my top picks and their tested reviews are as follows:

Keystone KSTAT12-1C (60.5 dB)

I like the easy cleaning feature included in this brand. It has a front-mounted removable filter that collects dust in and around it.

One of the major sources of concern with wall AC is how to clean the parts. This is because you cannot access the parts compared to window-mounted ones.

It has three operating modes and speeds for the blower fan that allows for reducing the noise levels. It has a thermostat-enabled remote control that helps in the even distribution of cool air in the room.

The noise level is a bit higher than the other brands in its category, 60.5 decibels.

Koldfront WTC12001W

This product has high cooling and heating capacities of 12,000BTU and 10,600 BTU.

When at the highest speed, the noise level becomes quite high. You cannot talk at an average voice level when it’s in this mode. Sometimes, you may need the room to get cool faster when you’re just coming in and will have to increase the speed. Doing other things like watching TV can be frustrating at such a time.

But after the room gets cooled and you reduce the speed, the noise level reduces drastically. Also, at low speed, the 4-way air directional louvers help to circulate cooled air effectively. It has a good energy rating for a product of its size, capacity, and price.


This is the quietest AC in this category. When it’s working at low speed, it’s like a quiet hum. The two lower speeds are quieter; you could sleep like a baby when it’s working. It also has 4-way air deflection louvers for easy distribution of cooled air in the room.

Another advantage it has over the others is its high energy rating of EER 10.6. It cools the space efficiently and has a removable air filter casing for easy cleaning.

EER and CEER Explained

The Energy Efficiency Ratio (EER) and CEER are used to determine the air conditioner’s efficiency. The higher the EER value, the more energy efficiency for the AC. The general standard EER value is about 9.7. A frequently used efficient AC helps to save more money over time.

Wall vs. Window Air Conditioner

These two AC types similar in some ways, but they have a few differences, which are:

1.     Cooling Capacities

Window ACs (these are the quietest ones) cooling capacity ranges from 5,000 and 34,000BTU, while the wall AC ranges from 8,000 to 24000BTU.

2.     Energy Ratings

The energy rating for wall air conditioners is higher than in window AC. This is because wall ACs have a tiger fit into the wall than the windows AC. This helps them to expend less energy in cooling the rooms compared to the window air conditioner.

3.     Wall Sleeves

Installation of a wall air conditioner requires a sleeve, and it is not a requirement with window ACs.

Benefits of a Wall Air Conditioner

  1. Since they are fixed in walls, they do not block view like the window AC.
  2. They give a tighter fit.
  3. They are a permanent installation.
  4. There is no form of bulkiness, and it looks modern because it sits flush with the wall.
  5. It’s a good choice for a small room.
  6. They are usually quieter compared to windows air conditioners.

Downsides of a Wall Air Conditioner

  1. They are louder when compared to split Air conditioners.
  2. The extra cost for the sleeve to be incurred is costlier compared to in windows AC.
  3. It’s harder to remove when the need arises, like when there’s a need to repair it.
  4. Wall air conditioners are a permanent method that will require more effort to close up the hole in the wall if there is ever a need to remove it.
  5. They have a limited cooling capacity option compared to the others.

In Conclusion

So I hope this information helps! Those hot days are always around the corner, so it’s better to be safe than sorry with a new, quieter AC unit at home and in the office. If you already have an AC but are looking for ways to make it quieter, check out this comprehensive guide on that topic as well. Talk to you soon!

Peter Baron

I learned how to fix many appliances while working part-time in a repair shop. Appliance Solver is the result of this experience, coupled with my interest in writing helpful content online. When I'm not fixing stuff, I'm usually either playing with my kids or on a walk with my golden retriever. Doesn't get much better than that.

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