{Top 5} Best Air Conditioners for Sliding Windows (2023)

Are you are hunting for the best air conditioner for a vertical-sliding window? If so, you are at the right place!

In this post, we will take a look at the {Top 5} Best Air Conditioners for Sliding Windows available in the market today. 

We will provide detailed information about each air conditioner to help you choose the best one for your needs. 

Let’s dive in and find the right air conditioner for your sliding window!

{Top 5} Air Conditioners for Sliding Window: An Overview


AC's Image

AC's Name

Cooling Power

Coverage Area

Noise Levels


Overall Rating

Check Price link


Editor’s choice!⭐


10,000 BTU

450 sq ft

72.3 dB




Editor’s 2nd choice!

Koldfront CAC8000W

8,000 BTU

300 to 350 sq ft

56 dB




PerfectAire 3PASC10000

10,000 BTU

450 sq ft

66 dB




Keystone KSTSW08A

8000 BTU

350 sq ft

59 dB




Arctic King 10,000 BTU

10,000 BTU

450 sq ft

63.7 dB

(10.4 EER), (9.5 CEER)


The 5 Best ACs for Sliding Window (Review)

Here are the full reviews of these five casements window air conditioners.


Editor’s choice!
  • Energy Efficient
  • Has a rating of 4.4 out of 5
  • Doesn’t take much time and effort to install and operate
  • Ideal for cooling large rooms up to 450 sq. ft.
  • Becomes noisy at high fan speed
Cooling Power10,000 BTU
Coverage AreaUp to 450 sq ft
Unit’s Dimensions14.5″D x 23.5″W x 20.25″H
Weight72 pounds
Noise Levels72.3 dB
Seasonal Energy Efficiency Ratio (SEER) 10.4
Voltage requirements115 Volts

This FRIGIDAIRE FFRS1022R1 window air conditioner for sliding windows is one of my favorite ac units. With 10000 BTU cooling power, it effortlessly cools rooms up to 450 square feet. It requires a standard 115V electrical outlet to operate.

The air conditioner has multi-speed electronic controls with a 24-hour on/off timer. The FRIGIDAIRE FFRS1022R1 is pretty energy efficient, thanks to its Energy Saver mode, which helps to conserve energy and reduce costs over time. This mode automatically adjusts the temperature to maintain a comfortable environment while minimizing energy usage. I used this unit for almost three months during the summer and it only cost me $31 to $33.

FRIGIDAIRE FFRS1022R1 casement window air conditioner

In addition to its various features, it also has a Seasonal Energy Efficiency Ratio (SEER) of 10.4, which indicates its level of efficiency.

Another noteworthy feature of this AC unit is its dehumidification function, which removes up to 3.4 pints of moisture per hour from the air. This is an important feature during the hot and humid summer months, as excessive humidity can lead to mold growth in your window ac.

However, as with any product, there are some drawbacks. One big issue with the FRIGIDAIRE FFRS1022R1 is that it is noisy, when running it on high I notice a noise level of 72.3 dB, which is pretty high.

Overall, the FRIGIDAIRE FFRS1022R1 is a solid option for those in need of a casement or sliding window air conditioning unit. If you are looking for sliding window air conditioner, this is a good choice to consider, check the link for best price:

May be helpful: A step-by-step guide to Install a Window AC on a Sliding Window

#2 Koldfront CAC8000W

Koldfront CAC8000W casement air conditioner
Recommended to buy!
  • Highly energy-efficient
  • Operates a low noise level
  • Nicely designed
  • Comes with a bunch of features
  • Poor customer support
Cooling Power8,000 BTU
Coverage Area300 to 350 square feet
Dimensions14.5″D x 23.5″W x 20.88″H
Weight75 pounds
Noise Levels56 dB
Seasonal Energy Efficiency Ratio (SEER) 11
Voltage requirements115 Volts

I recently bought the Koldfront FFRS1022R1 Air Conditioner for sliding window to review it but initially I had some doubts about this unit but now I am impressed with its performance. However, there were a few disappointing aspects as well.

Koldfront window air conditioner for slider windows

Anyway, the unit’s 8,000 BTU cooling capacity was perfect for the size of my room and effectively cooled the space during even the hottest of days. Its design allows it to fit windows that are 15-½ to 16-¼ inches wide, with a minimum height of 20-5/16 inches. So no matter where you want to place it, this air conditioner will likely fit.

Furthermore, this window air conditioner operates quieter than the pervious FRIGIDAIRE FFRS1022R1, its noise level is 56dB. Well, it is not as quiet as other window ac in the market, but when it comes to air conditioners for sliding windows, it’s quite good.

This unit’s remote control is incredibly convenient, allowing you to make adjustments to features and operation settings from up to 16 feet away. This feature adds to the overall ease of use and accessibility of the air conditioner.

But that’s not all – this Koldfront CAC8000W casement air conditioner is highly energy efficient, features like a check filter alert, sleep mode, and an energy saver mode that cycles the fan to save on energy your costs. The Check Filter Alert feature is a valuable addition, it basically guides when you to clean the filter to keep it dirt and dust free since a nasty filter can restrict cold air from window ac.

And ecocostsavings.com conducted a study which revealed that the annual cost of running window air conditioners ranges from $46.50 to $432.75. However, the Koldfront unit only costs $71 per year, making it a highly cost-effective option.

Speaking of sleep mode, you’ll love how it adjusts the temperature periodically by 2°F before returning to your set temperature after six hours, ensuring you’re resting comfortably while also saving on energy bills. 

Well its drawbacks is that some buyers have reported that the unit displays an error code indicating a refrigerant shortage after just a few months of use. 

An additional drawback of this Koldfront CAC8000W air conditioner for sliding windows is the poor customer support, which has also been mentioned by some buyers and I experienced this issue with this unit as well. This can be a significant issue if you encounter any problems with the unit or need assistance with installation or troubleshooting.

Despite these drawbacks, the air conditioner has received an overall rating of 4.1 out of 5. While this may not be trustworthy, but it is still a respectable rating and suggests that most of the buyers have found the unit to be effective and reliable. And to be honest, I doesn’t find any big issues with the unit rater than poor support.

Now, what do you think of this unit? In my opinion, the Koldfront CAC8000W Window Air Conditioner can be a good option for those who have horizontally sliding windows. It is also pretty affordable, you can check its current price from the link below:

#3 PerfectAire 3PASC10000

PerfectAire 3PASC10000
  • Quick and easy to set up
  • Its SEER rating is 13
  • 4-way adjustable air vents
  • Comes with a filter cleaning remainder
  • Make a loud noise
Cooling Power10,000 BTU
Coverage AreaUp to 450 square feet
Dimensions14.75″D x 23.5″W x 21″H
Weight77 pounds
Noise Levels66 dB
Seasonal Energy Efficiency Ratio (SEER) 13
Voltage requirements115 Volts

The PerfectAire 3PASC10000 is a powerful and efficient window air conditioner for slider windows. With its compact size and sleek design, it’s a great option for anyone who wants to stay cool without sacrificing style or functionality.

First of all, let’s talk about the design. The PerfectAire 3PASC10000 has a modern and stylish look that fits in with any décor. It’s also compact and lightweight, weighing 72 pounds, making it easy to move from room to room when needed. The control panel is located on the top of the unit, and trust me it is super easy to use, even for those who are not technically inclined.

PerfectAire 3PASC10000 sliding window air conditioners

Now, let’s get to the important stuff: how well does it work? The short answer is, incredibly well. This air conditioner can cool rooms up to 450 square feet, which is more than enough for most bedrooms, living rooms, or offices. It has three different fan speeds allow you to choose the level of cooling that you want. And the unit comes with a check filter which basically tell you when to clean the air filter.

One of the standout features of the PerfectAire 3PASC10000 is its seasonal energy efficiency ratio (SEER) of 13. This means it is highly efficient at cooling your space, and can help you save money on electric bill. And its noise level is 66 dB which is slightly high and can be disruptive.

Furthermore, you can set the unit to turn on or off at specific times, his feature can help save a bit of energy. It operates on 115 volts and is cULus listed, it means this unit meets safety standards in both the US and Canada. Installation is easy thanks to the included window mounting kit. Additionally, this sliding window air conditioners is slightly budget friendly.

If you are interested in buying this PerfectAire 3PASC10000 air conditioner for the sliding window, you can buy it from the link below.

#4 Keystone KSTSW08A

Keystone KSTSW08A
Perfect choice for medium-sized rooms!
  • Compact and portable
  • Filter Cleaning Indicator
  • Only cost around $72/Year to operate
  • Adjustable air circulation in four directions
  • Low moisture removal capacity
Cooling Power8000 BTU
Coverage AreaUp to 350 square feet
Dimensions23.5″D x 14.57″W x 20.87″H
Weight64.6 pounds
Noise Levels59 dB
Seasonal Energy Efficiency Ratio (SEER) 10.8
Voltage requirements115 Volts

This KSTSW08A Slider Casement Window Conditioner from Keystone perfect and convenient option for small to medium sized rooms.

This air conditioner is made by Keystone and has a cooling power of 8000 BTU, ideal for rooms up to 350 square feet.

One of the notable features of this sliding window air conditioner is its 3-in-1 functionality. Not only does it provide powerful cooling, but it also works as a dehumidifier with a capacity of up to 0.9 liters per hour.

Keystone KSTSW08A vertical sliding window air conditioner

Well, it may not be sufficient for areas with high humidity levels or for those that require a high level of moisture removal. Furthermore, the unit has a energy-saving mode that helps reduce energy consumption and save a ton in the long run. In addition, it is also packed with 4-Way air direction control.

Clean Filter Alert is another great feature that notifies you when it’s time to clean the filter, ensuring the air stays clean and free of dust, debris and contaminants. Which in turn keep your window ac quiet and also saves energy.

When it comes to ratings, the Keystone KSTSW08A 8,000 BTU Sliding Window Air Conditioner receives an impressive score of 4.5 out of 5 stars, reflecting its exceptional quality and effectiveness. However, it’s worth noting that the unit has a relatively low overall rating of just 47.

Talking about its energy efficiency, it is pretty good. This air conditioner only costs around $72 to run annually, which is significantly less than many window air conditioning units out there.

Overall, the Keystone KSTSW08A 8,000 BTU Window Air Conditioner for Vertical Sliding Window is a great choice for anyone in need of a reliable, easy-to-use, and energy-efficient air conditioning unit for medium-sized rooms. However, its dehumidification capacity is very low. Its noise level is neither too loud nor too silent.

So if you’re searching for a sliding window air conditioner for a room size of 350 square feet, the Keystone KSTSW08A is an excellent option to consider.

#5 Arctic King 10,000 BTU Casement Window Air Conditioner

Arctic King 10,000 BTU Casement Window Air Conditioner
Cheapest one!
  • Easy to operate
  • Slightly efficient
  • Pretty heavy
  • Little Noisy
Cooling Power10,000 BTU
Coverage AreaUp to 450 square feet
DimensionsH 20.9 in, W 14.6 in, D 23.5 in
Weight84 pounds
Noise Levels63.7 dB
Seasonal Energy Efficiency Ratio (SEER) (10.4 EER), (9.5 CEER)
Voltage requirements115 Volts

Our SPA team recently purchased this Arctic King 10,000 BTU Casement Window Air Conditioner, and we are thrilled with its performance. It quickly cooled my 180 square foot room. By the way, it can cool up to 450 square feet of space.

One of the features I love is the electronic controls and remote control, which makes it easy to set the comfort level I prefer. I can precisely control the temperature and fan speed from across the room, without getting up and manually adjusting the unit. The fresh air ventilation system also ensures that the air in my room is always clean and healthy.

While the Keystone KSTSW08A 8,000 BTU Sliding Window Air Conditioner has its notable advantages, there are a couple of drawbacks to consider. Firstly, it is on the heavier side, weighing approximately 84 lb. This can pose challenges during installation and mobility if you need to move it. Additionally, the unit can be a little noisy at times, which may be a concern for some users.

The Arctic King 10,000 BTU Casement Window Air Conditioner also features an automatic slinger-up system. It basically helps in removing excess moisture from the air by slinging it over the condenser coils. This prevents water build-up and the growth of mold and mildew.

Overall, the unit is nice and considerate. I would recommend the Arctic King 10,000 BTU Casement Window Air Conditioner to anyone who is looking for an easy-to-use, efficient, affordable, and reliable air conditioner for a sliding window. It currently costs $415. You can check its current price from the link given below:

Factors to Consider When Buying an Air Conditioner for Sliding Windows

Choosing the right air conditioner for sliding windows can be a daunting task. This is due to the fact that not all air conditioning units are specifically designed to fit sliding windows, and selecting the wrong one can result in installation issues, poor performance, and higher energy costs.

Here, we will discuss the factors to consider when choosing an air conditioner for sliding window:

Dimensions of the unit

When purchasing an air conditioner for sliding windows, the dimensions of the unit should be the first factor to consider. It is important to know the size of your window so that you can choose the appropriate air conditioner size. 

The height, width and depth of the unit should match or be less than the measurements of your sliding window.

A unit that is too large won’t quite fit in the window. To determine the correct measurement, measure the top, bottom, left and right sides of the window that opens from inside the house. 

Leave some space between each side to ensure proper installation. After taking all measurements, match them to the listed dimensions of the unit.

Cooling capacity of the unit

The second factor to consider is the cooling capacity of the air conditioner. This is determined by the size of the room you want to cool. 

A unit that is too small will not be effective in cooling, while a unit that is too large will consume more energy and will lead to higher electric bills.

To determine the appropriate size, measure the square footage of your room and refer to the manufacturer’s size chart.

Here are the preferred sizes according to the size of a room:

Energy Efficiency

When purchasing an air conditioner for sliding windows, it is important to keep energy efficiency in mind. Go with a unit with high energy efficiency ratings, as they consume less energy and result in lower electricity bills.

You can identify the most energy efficient air conditioners by looking for the Energy Star label, which indicates that they meet strict energy efficiency guidelines established by the Environmental Protection Agency (EPA).

Higher efficiency units are tend to be more expensive, but they will save you a lot of money in the long run by reducing your electricity bill.

Noise Levels

When buying an air conditioner for sliding windows, a crucial factor to look is the noise level. You want a unit that won’t be too loud and disruptive to you or anyone else in the area. Keep in mind that higher decibel levels indicate more noise.

Units with higher decibel ratings can range from 60 to 70 decibels, which is comparable to a conversation in a quiet room. Meanwhile, units with lower decibel ratings range from 20 to 40 decibels, which is equivalent to a whisper or rustling leaves.

Be aware that some manufacturers may list a maximum noise level, while others list an average. To get a better idea of ​​how noisy a unit makes, it’s helpful to read reviews from customers who have bought and used it.

Related: How long do window ac last?

Window AC for Sliding Windows; Wrap Up

To sum up, the Top 5 Best Air Conditioners for Sliding Windows in 2023 are chosen with great care, based on their excellent performance, high efficiency, and user-friendliness. 

These air conditioners possess the capability to cool down a room effectively and quietly, while also being easy to install and maintain.

Whether you’re searching for an energy-efficient option or a unit with a stylish and modern design, you can find an air conditioner that meets your requirements on this list.

By purchasing one of these top-rated air conditioners, you can be confident in staying cool and comfortable throughout the summer season.

Explore more about Window AC:

David Jack

David Jack

David Jack is a veteran when it comes to air conditioners, he love helping people find solutions to their problems with AC units. His specialty is helping people find the right Air-Conditioner for their needs, whether that means replacing a broken unit or adding on to an existing system. He is also great at diagnosing problems and fixing them quickly. He learned this from my father Jack Smith who was an air conditioner repairer, he has 2 years of experience in this field.

1 Comment
  1. I appreciate you sharing this blog post. Thanks Again. Cool.

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