Out of 5+ million air conditioners being sold in the US in 2019 (Source: statista.com), almost a million of them were the AC units are mounted on a window.
Why are window air conditioners so popular?
Well, that’s simple. The best window air conditioners are:
- More energy-efficient than portable air conditioners.
- Much easier to install (and a lot cheaper) than central AC units or split-system AC units.
- Do a tremendous job of cooling down 1, 2, or even 3 rooms.
Example: You can get a 10,000 BTU window air conditioner with a 12+ EER rating for less than $500.
You can DIY window air conditioner; thereby, you save $1,000s compared to mini-split or central AC systems.
Obviously, some window units are better than others. You also have to know a thing or two about:
- How many BTUs do you need?
- What type of windows you have?
- What does the EER rating really mean electricity-wise?
Air conditioning technology has really evolved in recent decades:
We at LearnMetrics take a look specifically at HVAC metrics. By comparing specifications sheets of over 70 window air conditioners (by Midea, LG, Frigidaire, Haier, and so on), we created a list of the best window AC units to buy in 2021. You can fast-forward to the list here:
Nonetheless, before we go to the best window air conditioners, we’ll quickly go over some specs we took into account.
When buying the best window air conditioner, it pays off to know the basic things like BTU, EER, relevant add-ons (such as dehumidifier function and even heater function).
Below the comparison table of the best window air conditioners, you’ll find reviews of each window AC unit.
Window Air Conditioner Buyer’s Guide (5 Key Factors)
This window air conditioner buyers guide is based on two parts:
- Your requirements (that’s your input). You can’t just pick any window AC unit with great specs; we’ll look into how many BTU unit would be best for your room/apartment size what type and dimensions your windows are. Especially measuring the window width will help you choose a window unit that fits well.
- Window AC unit specs (that’s our input). We’ll look into which are the most energy-efficient, quiet, and capable window air conditioners currently on the 2021 market, compare how much you’re looking to spend on the unit itself and the yearly electricity bill, and explain a bit what the specs-wise advantages of all the models are.
Before going through the best window AC unit list, we have to get an idea of what capacity (in BTU) would be best for you, what kind of windows you have, which window models have above 10 EER energy efficiency, what the price ranges are and what add-on (such as dehumidifiers, heaters) would make sense to you.
1. Capacity In BTU: How Many Square Feet Are You Looking To Cool Down?
Obviously, big apartments need a high-capacity window air conditioner, and small rooms need a low-capacity one. However, even in 2021, the No. 1 mistake people make when buying a window AC is misjudging how large a window AC unit they need.
Getting a too-large unit will needlessly spend too much electricity, and getting one that’s too little (to save money, space) might not be enough to cool down your home properly.
There are two standard questions here: ‘How many square feet does a 10,000 BTU window air conditioner cool down?’ or ‘I have 2 rooms with combined 500 square feet. Will a 10,000 BTU window air conditioner be enough?’.
To once and for all clear all the mess about the capacity up, let’s make this as simple as possible.
The general eco-friendly rule is to multiply the size of rooms you want to cool down (in sq ft) by 20. For example, if you have a 500 sq ft room, you multiply that number by 20 and get 500*20 = 10,000 BTU. You will need a 10,000 BTU air conditioner if you want to be really eco-friendly.
However, here’s the golden rule: If you don’t want to sweat about buying a too-small window unit, multiply the square footage by 30. For a 500 sq ft room, that would mean getting a 500*30 = 15,000 BTU window air conditioner.
Here’s a quick BTU calculator you can freely use. Just input how many square feet you’re looking to cool down, and the calculator will tell you how many BTU window air conditioners you should get.
Getting a bit bigger window AC unit will be especially helpful if you have a high ceiling, sunny location, or live in a hot climate (Texas, for example). In any case, it’s better to have 2,000 BTU too strong of a window air conditioner than to have a 2,000 BTU too weak one.
2. Types Of Window Air Conditioners (Standard, Sliding, Casement)
There are different window air conditioners for different window types. The most common window type is a so-called double-hang window. Most of the (horizontal) window AC units are designed to fit these standard windows.
Be aware of the window dimensions, however. A standard-sized window unit will best fit window 23-inch to 36-inch wide windows. The additional free space that may be left is filled with a cover.
Example: You have measured the dimensions of your window. It’s 30 inches wide. You can buy a standard-sized window AC unit for a minimum of 23-inch and maximum 36-inch windows. When installing, you mount the window AC unit (that’s 23-inch wide) on the window and use the included kit to cover those 7 inches that are left.
Make sure to mount the window AC unit in the center of the window. After that, use the window kit to bridge those 3 1/2” on the left and right side of the device:
The height of the window air conditioner unit is nothing to sweat about. The average height is about 15 inches, which is more than enough to fit a wide range of standard window dimensions used in the US.
Sliding Or Casement Windows
More than 80% of the windows in the US are double-hung. However, a small percentage of windows are sliding windows, and some people even have the European-style casement windows installed.
Obviously, the standard horizontal window AC units are a bad fit for sliding and casement windows. That’s why some brand offers the so-called ‘vertical’ window air conditioner. In short, they are the tall window AC units that fit perfectly into sliding or casement windows.
To install a vertical window AC unit, the minimum window width has to be at least 15 1/2”. If it’s wider, you use the window kit to cover the extra window space. If it’s narrower, you can’t really install a window AC and have to look for alternative types of air conditioning (a portable AC unit might be a better idea, for example).
The minimal window height for a casement AC unit is about 21 1/2”. That’s a ballpark figure, but every brand deviates very little from this minimum height.
3. Energy Efficiency: How Much Does It Cost To Run A Window Air Conditioner?
The window air conditioners are the most efficient stand-alone type of air conditioners. Being mounted on a window has a big advantage; you can directly transfer the hot air outside (the outer part of the window AC unit) while still technically inside (the inner part of the window AC unit that faces the room in).
The most commonly used metric to measure how energy efficient an air conditioner is Energy-Efficiency Ratio or EER for short. EER can be calculated by dividing the capacity (in BTU) by overall power (in Watts).
Example: A 10,000 BTU window air conditioner with overall power of 1,000W has an EER rating of 10. Here’s how the EER calculation goes:
EER = 10,000 BTU / 1,000W = 10
The average EER rating of window units is about 10. In comparison, the average EER rating of portable air conditioners is 8.5. That’s a 15% energy-efficiency difference.
You’ll also notice that some high-end window AC units can have extremely high EER rating by implementing inverter compressors.
The perfect example is the #1 choice of the best list of window AC units below; the LG LW1217ERSM has a 21.1 EER rating. This is quite an incredible achievement, and all the thanks go to LG’s compressor.
The chart below made for a 10,000 BTU window AC unit illustrates how many electricity dollars you’re going to spend given the EER ratings from 8 (very inefficient) to 14 (very efficient). These costs are calculated based on the device running for 8 hours per day for 3 months, with an average kWh price of 13 cents:
Most of the 10,000 BTU window air conditioners will add less than $100 to your yearly electricity bill.
Nonetheless, there is a significant difference between a 10 EER window AC and a 14 EER one. EER 10 will spend $94, while EER 14 will spend only $67 for the same cooling effect.
That’s a $27 difference in one year. In 10 years (the better window AC units can last for 20+ years), that’s a $270 difference. That’s why picking a window unit with high EER is an astute long-term investment.
Note: In the specification sheet, you will sometimes see a SEER rating for a window air conditioner. SEER stands for Seasonal Energy Efficiency Ratio and measures energy efficiency throughout the air conditioning season (3 summer months). It’s an even better estimate of how capable an AC unit is in utilizing energy. Nonetheless, for all intents and purposes, the EER rating is still the golden standard.
4. Price Range: How Much Do Window Air Conditioners Cost?
The window air conditioners are quite inexpensive compares to the portable AC units and especially compared with the central air and other split-system units.
In fact, taking into account the high energy efficiency and optimum price, the window units are the most buck-efficient air conditioners in general. That’s also why almost 1 million of them are being sold every year.
The price of a window air conditioner depends primarily on the capacity (BTU), and secondarily on EER, quality of materials, noise levels, and, not insignificantly, on the brand.
Here is a table of how much 6,000, 8,000, 10,000, 12,000, and 15,000 BTU window air conditioners cost with cheap, average, and premium price ranges:
|6,000 BTU||$200 to $250||$250 to $350||$350 to $500|
|8,000 BTU||$250 to $300||$300 to $400||$400 to $550|
|10,000 BTU||$300 to $350||$350 to $450||$450 to $600|
|12,000 BTU||$350 to $400||$400 to $500||$500 to $700|
|15,000 BTU||$400 to $450||$450 to $550||$550 to $600|
Obviously, these are rough estimates of how much window air conditioners of different capacities can cost. On top of that, the ones with add-ons such as additional dehumidification or heater option do command a higher price.
When deciding how much to spend for a window AC unit, it pays off to know how long the window air conditioners last.
The answer? 10 years, 15 years, the premium ones even up to 20 years. It depends primarily on the built materials. For example, premium brands like LG, Frigidaire, and Friedrich Chill use higher-quality materials that can last for 20 years.
Other brands that offer cheaper window AC units such as Della, Koldfront, and Danby won’t last as long. That is precisely why they have a lower price. They are budget-friendly but not quality-oriented.
5. Add-Ons And Extra Features (Dehumidifier, Heater)
Obviously, if you have a working HVAC device such as a window air conditioner already mounted on your window sill, it makes sense to build in some other HVAC properties.
In translation: A window AC unit can serve as a dehumidifier as well as a heater. Every unit can also create a light breeze with the inner fan.
That’s why we talk about:
- 3-in-1 window air conditioners: AC + Cooling Fan + Dehumidifier.
- 4-in-1 window air conditioners: AC + Cooling Fan + Dehumidifier + Heater (extremely rare).
Window air conditioners with heaters, however, are rare (but beneficial). Usually, their price is quite high, you need a non-standard 230V outlet, and they are rarely as energy efficient as window AC units without heaters.
9 Best Window Air Conditioners To Buy For 2021 Summer Heat
#1 Midea U Inverter MAW08V1QWT (First U-Shaped AC With Open Window Flexibility)
In 2021, the Midea U Inverter (MAW08V1QWT model) is all the rage. Midea took all the technological advancements in the air conditioner industry in the past 5 years and combined them in one window air conditioner. It’s no wonder why it has earned numerous prizes for being the ‘Best Window Air Conditioner Of 2021‘.
From the specs point of view, the most important part of the Midea U Inverted unit is the advanced DC inverter technology. Due to its energy efficiency, the Midea U Inverted earns the ‘ENERGY STAR Most Efficient 2021 Certification‘.
Not only does it use 35% less energy (with the highest CEER of 15.0), it is also as quiet as a mouse. In fact, the compressor produces 42 dB of the noise of the low setting; that is 9 times quieter than a standard device.
The high-efficiency, inverter compressors, and ultra-low noise levels are what the HVAC experts love. What is more, this window air conditioner is beloved by homeowners because of the following 3 features:
- U-shaped design. Standard window AC units look old-school; the Midea U Inverter has a modern and aesthetic design. It looks good on your windowsill.
- Convenient with Smart Control. It’s Wi-Fi-enabled; that means you can use MideaAir iOS or Android app and control it with ease.
- Flexible installation. The installation is straightforward, pretty much every family can do it on their own, and you can even have an open window while it’s running.
All in all, the Midea U Inverter is the best window air conditioner in 2021 based on both specifications and the extra features homeowners love. It’s the most efficient, the quietest, and the best-looking air conditioner you can easily install on your windowsill. You can get it in 8,000, 10,000, or 12,000 BTU capacity here:
#2 LG LW1216ER (Most Popular Window AC Unit In 2021)
In short, the LW1216ER is spectacular no matter which HVAC metric you look at. At the very core of this superb LG window air conditioner is the new rotary compressor the LG has recently introduced. This compressor just shoots all the specs up in a significant way.
The energy efficiency rating EER is 12.1. This makes the LW1216ER one of the most energy-efficient window air conditioner. The average EER of a window AC unit, for comparison, is about 10.
That means you will likely save more than $250 in 10 years just because of the exceptionally high and eco-friendly LG compressor. The estimated yearly costs are below $80; this kind of tech was impossible to conceive even a few years ago.
It comes with a series of must-have features, such as Auto Restart, 24h On/Off Timer, and Easy-Clean Air Filter:
In addition to the most eco-friendly air conditioner, the LW1216ER window AC unit also has a built-in dehumidifier. The dehumidifier itself is one of the best as well; capable of extracting 3.8 pints of water out of your indoor air every hour.
The noise levels are very low. The LG provides a very detailed look at how quiet the LW1216ER is. The decibel levels of 58/54/50/44 dB for high/medium/low/sleep settings, respectively.
Another area that LG LW1216ER excels at is user-friendliness. SmartThinQ technology truly makes the LW1216ER model a smart window air conditioner.
That means you can change all the settings via your smartphone (if you choose the Wi-Fi version, of course). You get an app and can raise or lower temperature just with a click. If you want, you can also connect Alexa and Google Assistant to lower the temperature just with the sound of your voice.
As you can see from the photo of the control panel above, you have quite a few settings to choose from. These include cooling, energy-saving program, fan, dry (dehumidifier), clean filter, sleep, Wi-Fi (for SmartThinQ tech), and a timer.
It also comes in a range of capacities; you can choose between 5,000, 6,000, 8,000, 10,000, 12,000 , 15,000, 18,000, 24,500 BTU models.
All in all, LW1216ER is the most popular window AC unit you can get. The highest energy efficiency is achieved at very low noise levels and at an affordable price. The ability to connect the window air conditioner via Wi-Fi with your smartphone makes using it look and feel effortless.
#3 Della 048-TL-WAC6K (Best Cheap Unit)
In the world of window air conditioners, the price usually dictates the specs. That’s why the Della 048-TL-WAC6K model is so incredible. It delivers exceptionally high HVAC specs at a fairly reduced rate.
At the same time, Della offers a wide range of window AC capacities, namely 5,000, 6,000, 8,000, 10,000, 12,000, and 15,000 BTU units. You can cool down a small 150 sq ft room and several rooms with a net square footage of over 500 sq ft.
Despite the low cost, the Della 048-TL-WAC6K has an EER rating of 12.2. This makes it the second most efficient window-mounted AC unit on the list. In comparison with a standard window air conditioner, you’re looking to save an additional $20/year on the electricity bill.
In addition to being eco and budget-friendly, the Della window AC unit is easy to run with a digital screen and easy to maintain with the easy-clean filter:
In addition to cooling down your house, the Della 048-TL-WAC6K also serves as a dehumidifier. Like a dehumidifier, it’s less capable than a standard $200 dehumidifier. It has a dehumidification rate of 1.9 pints per hour. Nonetheless, you don’t have to spend those extra $200 to get a stand-alone dehumidifier.
It is also the second most quiet window air conditioner. The decibel levels of 55/53/51 dB make it even quieter than our #1 LG pick. That’s a surprisingly silent HVAC device given the high 240 CFM airflow.
What is more, you even get an installation kit in the package. This is what it looks like:
In summary, Della is the best cost-benefit window AC unit you can find. The great specs, wide BTU range, and the EnergyStar and UL certification make it a powerful and durable window air conditioner without matching this price.
#4 Friedrich Chill CP06G10B (Best Through-The-Wall Air Conditioner)
As you may know, some window air conditioners can be installed through the wall instead of installing them on a window. Friedrich Chill has designed the best through-the-wall air conditioner with their CP06G10B model.
Of course, that doesn’t mean that you can’t install them on a window sill as well. However, when installing the Friedrich Chill through-the-wall AC unit, you must be careful about the wall thickness. You can read more about this in our selection of the best through-the-wall AC units here.
The wall has to be 7 1/2” or less thick. If you have a thicker wall, you really should be looking to install it on a window instead. Here is how it looks when mounted on a window sill:
It has superb energy efficiency with an EER rating of 11.2. For a though-the-wall AC unit that can double as a window air conditioner, that is quite an enviable efficiency.
Friedrich Chill has also managed to create a wide array of these through-the-wall air conditioner capacities. You can pick among the 5,200, 6,000, 8,000, 10,000, 12,000, 15,500, 19,000 and even 24,000 BTU units. The advantage of installing a window air conditioner through the wall is that you can get a capacity of up to 24,000 BTU.
The bad side of the Friedrich Chill CP06G10B is the steep price. Precisely because the air conditioner can be installed through the wall, the device can command much higher prices. For example, it’s not unusual for a 10,000 BTU Friedrich Chill unit to cost up to $550.
Nonetheless, if you want to use a through-the-wall air conditioner, the Friedrich Chill CP06G10B model is the way to go.
#5 Frigidaire FFRS1022S1 (Best Vertical AC Unit For Casement Or Sliding Windows)
The Frigidaire FFRS1022S1 is a favorite model of people who either have casement or sliding windows. If you don’t have a standard double-hung window, you get fewer options when it comes to vertical window air conditioners that can be mounted on a casement or sliding windows.
The Frigidaire FFRS1022S1 is designed only to fit a casement window. You can only install the Frigidaire on casement windows that are from 15 1/2” or wider. The height of the casement window (minimum of 21”) is usually not problematic.
The Frigidaire vertical air conditioner comes with two distinct advantages; an excellent dehumidifier add-on and the highest airflow of 323 CFM.
Its great rating is also thanks to the low decibel levels. Namely, the 55/57/59 dB noise levels for low, middle, and high settings make 55/57/59 dB make this vertical AC unit a quiet one.
Nonetheless, it’s not all shiny: You have that trio of high price, only an average EER of 10.4 and weight. This is a heavyweight 72 lbs vertical air conditioner with 10,000 BTU capacity.
However, the vertical units are known to be heavier, more expensive, and without the really high EER rating, other standard window units are known for.
#6 Frigidaire GRC1044T1 (The Quietest And Most Elegant)
Now, the Frigidaire GRC1044T1 is a head-turner. Just one look at it, and you’ll notice that having this AC mounted on your window is not an intern design hindrance. It’s an elegant and sleek appliance that can enrich the overall room atmosphere (and cool air very efficiently).
About that energy efficiency: the Frigidaire has managed to create a window unit with an EER of 12. That’s superb, especially taking into account the powerful 285 CFM airflow the GRC1044T1 model generates.
This unit can be installed on windows with a minimum width of 24” and a maximum width of 40”. What really matters, however, is how fancy a window air conditioner can look:
As you can see, it’s also made out of high-quality materials. This is a premium window unit that’s quite reasonably priced.
What’s even more, it has one of the most powerful dehumidifiers for a window AC unit. The built-in dehumidification function can remove up to 3 whole pints of water out of your air. That’s quite a large number ever for a $300 stand-alone dehumidifier.
However, what brings the ranking of the Frigidaire window unit down is the mediocre user rating of 3.6/5. Going through reviews, you can see many people received damaged goods, which is far from ideal.
You can check the list of the quietest window air conditioners here.
Nonetheless, with a bit of luck, you can order a 6,000, 8,000, 10,000, or a 12,000 BTU window air conditioner and receive it in one piece. In any case, due to its modern and minimalistic design, the Frigidaire GRC1044T1 received the price of being the most beautiful window unit on the market.
#7 LG LW6017R (Most Popular And Quiet LG Unit)
Obviously, LG is a company that makes the best HVAC devices. The #1 LG LW1217ERSM is a clear indication that; the whole Dual Inverter tech was their idea.
Nonetheless, the LW1217ERSM model is not the most popular choice. This price goes to the #7 on our list: the LG LW6017R.
What makes the LW6017R so popular? Well, it’s down to 3 things:
- Reliability of LG brand.
- Great specs (EER = 11.5, for example).
- Lower price than premium LG window unit.
The low price for an 11.5 EER energy-efficient window air conditioner made and product by LG is what most people buying a window unit are looking for.
With the maximum noise levels of 56 dB, the LG also created the quietest window air conditioner you can buy. Obviously, no one likes to have a noisy device. Being so quiet even at a high setting is also why people love this LG window device so much.
The dehumidification function goes hand-in-hand with the air conditioning function. The LW6017R model is capable of extracting up to 1.8 pints of water from humid air every hour.
Being light (the 6,000 BTU unit weighs only 39.6 lbs) also helps with the installation. All in all, it’s no wonder why this straightforward and simple device is the most popular one as well.
#8 MIDEA MAW08R1BWT (Cheapest One With 10,000 BTU Unit Almost As Low As $300)
Midea is a less known brand in the HVAC world. However, they have managed to put together quite a nice device with superb specs. Their best model is the ‘Easycool MAW08R1BWT’.
What is really incredible, like off the bat, is that it has an extremely high EER rating of 12. This is a very budget-friendly device. The 10,000 BTU Midea window air conditioner costs less than $350. Having such great energy efficiency at such a low price point is unheard of.
And get this; the MAW08R1BWT is also one of those 3-in-1 window units that include a dehumidifier. The maximum rate of dehumidification this unit can achieve is 2.54 pints/h. Not bad at all!
The installation process is quite simple. You even get the window installation kit with the purchase and can DIY the installation. When you’re done, the window unit should look something like this:
The series of certifications Midea has scored the EnergyStar, UL, and DOE certifications. Quite impressive, to say the least.
However, what has to be pointed out is that all these low-price high-specs do come at a cost. The MAW08R1BWT model’s materials are sadly not the premium materials LG devices are made out of. This window AC will likely not last for 20 years; however, you’re buying good specs for the next 10 years for this price. After that, most of these 2021 window air conditioners will be obsolete anyway.
The noise levels are a bit high as well. Here is the noise spectrum – 57.5/59.3/60.5 dB. 60 dB is not ideal in any case.
You can get the cheapest 5,000, 6,000, 8,000, 10,000 or 12,000 BTU unit with great specs but it won’t last for 20 years or more.
#9 Haier ESAQ406T (Well-Known Haier Unit)
Haier is one of the well-known HVAC manufacturers. The small 6,000 BTU ESAQ406T is one of the most well-rounded and simple window air conditioning units for quite an affordable price.
According to their 2016 rating, it has an extremely high energy-efficiency rating EER of 12.2. That’s actually the 2nd highest EER rating on the list.
Despite being a small device, however, the Haier ESAQ406T will only fit windows that are at least 26 inches wide. Most of these AC units fit windows that are 23” to 36” wide. Haier, on the other hand, created a unit that fits 26” to 40” windows.
Despite the good specs, however, the ESAQ406T model is not the most popular model anymore. Simply put, it is an older model that had remarkable specs even a few years ago, but the whole design is a bit outdated.
That’s why, despite the high EER 12.2 rating, Haier is at the bottom of the list.
Feel Free To Share Your Opinion
It took us quite a while to create this list. However, we might have missed a window AC unit or two. If you have found one with great specs that would be a good fit, you can share your opinion in the comments below.
Other articles of window AC units include:
- Quietest window air conditioners (with very low noise levels).
- Biggest window AC units (with over 20,000 BTU cooling output).
- Low profile window units (with only 3-inch profile).
- Vertical air conditioners (for minimum window width air conditioners).
- Combination of window AC and heaters.
- Smallest window air conditioners (with only 5,000 BTU cooling output).