Best Casement Window Air Conditioners – 2021 Round-up

For those who are reluctant to install an air conditioner in their home because of casement windows, we have a perfect solution for you this summer. 

A casement window air conditioner is a great way of bringing a breath of cool air in your home, that too, at an affordable price. 

With so many options available, picking the right AC can be time-consuming. To save you time and energy, we have compiled a list of some of the best options you should definitely check out.

Comparison of the Best Casement Window Air Conditioners

  • Casement and slider mounting options for easy installation
  • Strong construction for improved durability
  • Easy full-function remote control included
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  • Adjustable temperature settings of 62 to 83 degrees Fahrenheit
  • Up to 3 speeds fan and cooling mode
  • Up to 10,000 BTU cooling capacity
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  • Best for the Money
  • 4-way air direction controls for better airflow
  • Choose from 3 fan speeds for your home cooling
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  • Best 12000 BTU Casement Window Air Conditioner
  • Energy savings of more than 35 percent
  • Very quiet operating noise of only around 42dBA
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  • Best Small Casement Air Conditioner
  • Auto restart and sleep mode for energy saving
  • Everything needed for complete installation included
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What is a Casement Window Air Conditioner?

Since not every air conditioner is going to fit into a sliding window, you need to consider another option. The sashes of such windows cannot fit traditional window air conditioners inside them. To eliminate this problem, many brands have introduced slider or casement window air conditioners. Such units have a vertical orientation and are relatively longer than other types of units.

A casement window air conditioner can be 20 inches or more in height and comes with pre-cut inserts to securely hold the AC in the window frame. They stay in place and are a great alternative for homes that lack a central air conditioning system.

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How Do Casement Window Air Conditioners Work?

The air-cooling process starts by pulling the moving air in with the help of a blower. The air moves through an air filter that removes all the dust and unwanted particles. It then enters the cooling coil and drops in temperature after passing through it. The cool air is then finally blown back out into the room.

The working of this type of AC unit is quite similar to that of traditional window ACs. The only difference between them is the size and, of course, the method for installation. 

Review of the Best Casement Window Air Conditioners

Traditional air conditioners do not fit in sliding windows. However, this does not mean you don’t have any other option. Here are some of the best casement window air conditioners that can serve the purpose efficiently. 

Best Overall:
Frigidaire FFRS0822S1

FRIGIDAIRE FFRS0822S1 8000 BTU Heavy-Duty Slider Casement, Electronic, Remote Control Window Air Conditioner, 8,000, White


  • Comes with a reliable warranty
  • Noise levels are surprisingly low
  • Remote control operation for your convenience
  • User-friendly and offers various operating modes
  • Solid construction and features a double-wall thickness


  • A bit heavy
  • Installation can take time

What Recent Buyers Report

Users find this casement air conditioner extremely useful on hot summer days. According to them, the build is amazing, plus it provides exceptional features without being expensive. The incorporation of remote control functionality allows you to adjust the settings without getting up from the sofa. Moreover, you get to enjoy a warranty.

Why it Stands Out to Us

Frigidaire is not a new name in the industry. The company is well-known for manufacturing superior units with quality standards. This air conditioner is ideal for small to medium rooms of up to 350 sq ft. With 8000 BTUs of cooling power, it cools down the room within minutes. Other than the cooling capability, the unit is quite popular for its dehumidifying process.

It evenly distributes the cool air with three fan speeds. Moreover, you get full control over the temperature, thanks to the remote control functionality. You can make the adjustments while sitting on your sofa, thereby ensuring maximum comfort. Additionally, there are multiple energy-saving features, including sleep mode and energy saver mode. 

Bottom Line

An excellent unit, this air conditioner tends to last in the long run. Its durable build and energy efficiency have marked its position on the market as a reliable product. All in all, it is one of the finest deals out there. 

PerfectAire 3PASC10000

PerfectAire 10,000 BTU Slider Air Conditioner Window A/C - Casement, 10000, Gray


  • Tilt-out air filter for easy cleaning
  • Suitable for small to medium-sized rooms
  • Compact and reliable design that is easy to install
  • Operates at three-speed levels in both cool and fan modes
  • Portable thermostat technology to ensure complete room coverage 


  • Lacks heat mode 
  • Might get noisy at times

What Recent Buyers Report

A well-reviewed unit, this model is quite popular among users for its durable build and simple installation. They have appreciated its compact design that can easily fit a sliding window. Moreover, this AC evenly distributes cool air across the room to keep you cool on a hot day. 

Why it Stands Out to Us

The PerfectAire air conditioner is ideally designed to provide cooling performance for rooms up to 450 sq ft. It has a sturdy build, and the compact design can be easily installed. With 10000 BTUs cooling power, the model is suitable for different window types, thereby saving you from costly custom designs.

The unit also acts as a dehumidifier to provide a nice environment. The fan can be operated at three different speed levels according to your choice. Moreover, the temperature is adjustable, so you can customize your cooling needs. Last but not least, the AC comes with a reusable filter to ensure healthy and clean air. 

Bottom Line

If it wasn't for the noisy operation, this air conditioner would definitely be our favorite. With exceptional cooling power and portable thermostat technology, it is worth the investment. In short, there is no chance you will go wrong with this product.

Best for the Money:
Keystone KSTSW10A

Keystone KSTSW10A AC 10,000 Slider Casement Window-Wall Conditioner and Dehumidifier with 4-Way Air Direction Control for Small-Medium Rooms up to 450 Sq.Ft, 10000 BTU, White


  • Sturdy and silent in its operation
  • Comes with a built-in filter indicator
  • 4-way air-flow to cool down the room evenly
  • Energy-saver mode to cut down on your monthly bills
  • Sleep mode keeps you cool without any inconvenience 


  • Drains poorly
  • Vents are a bit difficult to adjust 

What Recent Buyers Report

With its reasonable price tag, this casement air conditioner has caught the attention of many new customers. Users are satisfied with the performance and loved how efficiently the unit cools down the room. Its silent operation keeps you cool without disturbing your sleep. Moreover, its energy-efficiency saves you from hefty bills every month. 

Why it Stands Out to Us

If you are looking for a reliable air conditioner that keeps you cool without breaking the bank, then you must get your hands on this unit from Keystone. The company is recognized for incorporating some exceptional features in their products. This model comes with a durable build and a nice design that is suitable for a home without traditional double-hung windows.

Its 10000 BTUs cooling power is just enough for a 450 sq ft room. You will find a washable filter that removes dirt and dust to provide clean air. The most amazing quality is its quiet operation. The sleep mode allows a sound sleep at night. Being energy efficient, the unit keeps you cool during the hottest parts of the day while slashing your monthly bills.

Bottom Line

One of the most pocket-friendly options, this air conditioner is the ideal choice for those on a tight budget. It is quite effective in cooling down small to medium-sized rooms while ensuring energy efficiency. 

Best 12000 BTU Casement Window Air Conditioner:
Midea U Inverter MAW12V1QWT

Midea 12,000 BTU U-Shaped Smart Inverter Air Conditioner–Cools up to 550 Sq. Ft., Ultra Quiet with Open Window Flexibility, Works with Alexa/Google Assistant, 35% Energy Savings, Remote Control


  • Simple and quick installation
  • Wi-Fi enabled for convenience 
  • Comes with a high cooling power
  • Extremely quiet and energy-efficient unit
  • U-shaped design allows you to open windows


  • Huge and a bit heavy
  • Falls on the higher end of the price spectrum

What Recent Buyers Report

Users are quite happy with the purchase. They just love the fact that this unit allows them to open their windows to enjoy some fresh air. It can be easily installed and controlled from anywhere, thanks to the Wi-Fi functionality. Moreover, it is extremely silent and, therefore, keeps you cool while letting you enjoy a sound sleep. 

Why it Stands Out to Us

There aren’t many casement air conditioners on the market that allow you to open windows after the installation. However, this model is different and offers everything you would want from a casement window AC. With 12000 BTUs of cooling power, the unit is capable of cooling down medium-sized rooms up to 550 sq ft. 

One of the best qualities is its energy efficiency. The incorporation of the DC inverter technology ensures 35% energy saving as compared to traditional models. You will love how quiet this air conditioner is. Additionally, the Wi-Fi control option allows you to control the settings from anywhere with just your smartphone. Thanks to the support brackets, the installation is a breeze.

Bottom Line

Another great air conditioner on the market, this model is surely an all-around performer. From the surprisingly amazing cooling tendency to the flexible design, and from energy-efficient operation to silent performance, it covers everything. 

Best Small Casement Air Conditioner:
Global Industrial MWDUL-10CRN1-BCJ4

Casement Window Air Conditioner 10, 000 BTU 115V with Remote


  • Compact and user-friendly 
  • Comes with an efficient sleep mode
  • Package includes the installation kit
  • No regular filter replacement required
  • Backed by a five-year warranty to ensure reliability


  • A bit noisy than other models on the list
  • Requires a minimum setting of 62°F to work properly 

What Recent Buyers Report

A very well-reviewed AC, this unit has lured many new customers with its powerful performance. What users really love about it is its easy installation and four-way airflow. You can easily adjust the settings from anywhere in the room. Moreover, the timer allows you to run the unit as long as you want.

Who Will Use This Most

One of the most compact and user-friendly air conditioners on the list, this unit is ideal for creating a suitable airflow during those hot summer days. Its 10000 BTU cooling power is enough for medium-sized rooms up to 450 sq ft.

The installation becomes very easy with the provided installation kit. Thanks to the user-friendly features, you can achieve the desired cooling experience. Turn on the four-way air direction to spread the cool air all across space. Thanks to the remote control, there'll be no need to get up from the sofa and make the adjustments. 

Another prominent feature is the auto-restart mode that allows the unit to restart in case of a power outage. Not to forget, there is a five-year warranty as well.

Bottom Line

An extraordinary air conditioner for everyday use, this unit is meant to serve you in the long run. Both the quality and design are commendable. So, if you want a budget-friendly and energy-efficient unit, this is a must-have.

Best Portable Air Conditioner for Casement Window:
Honeywell HL10CESWB

Honeywell Contempo Series Portable Air Conditioner, Dehumidifier & Fan with Dual Filtration System for Rooms Up To 350-450 Sq. Ft., Polished & Powerful (Blue/White), 10,000 BTU/450 sq. ft. (HL10CESWB)


  • Silent yet powerful operation
  • Digital display to make it user-friendly 
  • Incorporates dual filters to provide clean air
  • Portable and therefore, easy to move around
  • Eco-friendly and features adjustable temperature


  • Some quality control issues
  • Not suitable for large rooms

What Recent Buyers Report

Users appreciate the contemporary design and high-end build of this unit. They just love how quiet it is, which ensures a sound sleep after a tiring day. Moreover, it is very appealing to the eyes. The incorporation of dual filters also makes it quite suitable for those who are allergic to dust.

Why it Stands Out to Us

Honeywell is a renowned name in the industry that has made a name for creating exceptional models. This unit is specially designed to improve the lifestyle of people. Manufactured from high-quality materials, it is robust and user-friendly. The fan can be operated at three-speed levels as per your requirement.

There is a built-in dehumidifier with a continuous drain option. Thanks to the dual-filter feature, you will get clean and cool air every time you turn on the air conditioner. The filter is washable as well to allow easy cleaning. To make the installation easier, manufacturers offer a complete kit in the package. Moreover, the digital display and remote-control operation take comfort to a whole new level.

Bottom Line

With an attractive and polished design, this air conditioner truly elevates the interior of your house while keeping it cool all the time. With the cooling capacity and dehumidifying tendency in a single unit, this model is worth consideration.

Best 5000 BTU Casement Window Air Conditioner:
Keystone KSTAW05B


  • Comes from a reliable brand
  • Energy-efficient and quiet performance 
  • LED display to easily select the options
  • LCD remote control to bring convenience
  • Auto-restart mode remembers the setting in case of a power cut


  • Suitable for small spaces only
  • Installation can take some time 

What Recent Buyers Report

Just like our other products, this air conditioner has won the confidence of most users. According to them, it is robust, user-friendly, and effective in cooling down the room. The remote control functionality ensures comfort, and the energy-efficiency gives you peace of mind, knowing you will get a comfortable environment without breaking the bank.

Why it Stands Out to Us

Another reliable unit from Keystone, this air conditioner is specially designed to cool down small spaces on hot days. With a 5000 BTUs cooling capacity, the unit will effectively keep the room cool. You can easily adjust the settings with the help of a remote. Another noteworthy feature in the remote control is the temperature sensing "follow me" option. This feature allows the unit to read the temperature within the room and adjust easily.

It is a great option for those who want to cut down on their monthly bills. Moreover, the auto-restart mode is quite helpful in case of a storm, rain, or thunder.

Bottom Line

This fantastic air conditioner makes its way to our list for exhibiting an exceptional set of features. Not only is the cooling capacity enough for small spaces, but it also ensures a seamless operation without any inconvenience. 

How Do I Choose a Casement Window AC?

As mentioned above, a casement window AC is probably the best solution for house owners with casement windows. However, choosing the right one for your needs can be a bit of a struggle, especially when there are a plethora of options available.

A reliable air conditioner should check all the boxes of criteria for the best model. Therefore, here we have listed down the essential features that you must look for while making a purchase.

Easy to Install

Casement window air conditioners tend to be a bit heavier than traditional units. This can highly alter the ease of installation. Therefore, you should always look for a model that comes with easy installation steps and requires less maintenance. 

Silent Operation

When it comes to home appliances, noise is something that we all hate. The decibel rating of the quietest air conditioners generally ranges from 40 to 60 dB.

Therefore, you should always opt for a quiet model in your bedroom to enjoy a comfortable sleep at night.


It isn’t always necessary to remain cool while spending a fortune. Most of the models from reliable brands are designed to be energy-efficient.

It is suggested to pick a unit that comes with a government-approved ENERGY STAR label. 

Midea U Inverter MAW12V1QWT


A good warranty coverage improves the faith of customers in the product. Some brands offer better deals than others. Therefore, don't forget to take this factor into account.

Cautious Considerations to Keep in Mind

Investing in a superior casement window air conditioner can be highly rewarding. However, you must know some important factors regarding them in order to avoid any regret in the future. Here are some cautious considerations to keep in mind for a wise decision. 


Though not a big problem, casement window ACs tend to be a bit heavier than traditional air conditioners. They are relatively longer and, therefore, fall on the heavier side of the spectrum. This feature can directly alter the installation process. You may need someone by your side during the installation.

Mediocre Design

You should know that this type of air conditioner isn't the most attractive element of the household décor system. Such units generally feature a long vertical design that is not pleasing to look at. However, you can always remove it when not in use, like in winters.

Window Insertion

Casement window ACs are specially designed for sliding windows. Since they require an actual insertion in the windows, your window must be kept open to a certain extent. This way, the hot and humid air is likely to pour in while letting the cool air escape.

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How to Install a Window AC Unit in a Casement Window

With the summers approaching, it’s time to get a good window AC unit for your bedroom. Installing a unit in a casement window is usually a DIY task and doesn’t require professional help. Most of the models come with a detailed instruction manual as well. We have divided the whole process into some simple steps to make the job even easier for you.

1. First of all, measure the length and width of the inside of the window sill.

2. Now drill the holes in the frame and install it. Make sure to use the screws provided in the package to secure the housing or frame in the window.

3. Once the frame is properly fixed., it’s time to place the AC inside it. Slide it carefully as far as you can. If the frame is well attached, you won’t have any issues, such as the AC falling out.

4. Use a weather-stripping seal on the unit to protect it from harsh weather conditions. You are good to go now! 

In case you find these steps difficult, refer to the video below in order to have a full overview of what was just described. 


Casement air conditioners are an ideal option for rooms with sliding windows. While picking a model, make sure to consider various factors like ease of installation, cooling capacity, and smart-control features for an ideal purchase. Hopefully, this article gave you all the required information about these units, and you now know how to choose the right one for you.

People Also Ask

Having read multiple reviews on the internet, some of you might still be confused about the best casement window air conditioners out there. In this section, you will find answers to some of the frequently asked queries regarding them. Go through it in order to clear all your doubts.

What is a Slider Casement Window Air Conditioner?

Houses with casement windows require a casement or slider window air conditioner. Such units are designed for vertical openings. They are a bit heavier but work effectively in keeping the space cool on hot days. 

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What Type AC Fits in a Casement Window?

The sashes of casement windows do not allow a traditional window unit to fit into it. If you have a casement window rather than double-hung windows in your home, the only option for you is a casement window air conditioner. Specially designed for vertical openings, such units fit sliding or casement windows properly and ensure effective cooling.

Can You Install an Air Conditioner Sideways?

Absolutely not; while air conditioners can be stored or shipped by turning them on their sides, they should never be installed or run that way. Such orientation can damage the compressor mounting. Moreover, the unit's dehumidification system generally relies on gravity to take water away from the air conditioner. 

How Much Does an AC For a Casement Window Cost?

Casement window air conditioners are relatively cheaper than other types of air conditioners. Depending on the model and brand they come from, these units generally range from $138 to $502. Additionally, installation can cost you from $60 to $200. Such units are good for homes that don't have a central air conditioning system.