Top 10 Best Air Conditioner For Small Window Opening 2022

If you’re wondering whether you’d be able to find the best air conditioner for small window opening to keep your small room cool and tolerable during summer, we’ve got just what you need.

Using a window air conditioning unit is the best way to keep your room extra cool during the hot season. These units supplement central units and perfect for small or medium spaces. The best part is that they are affordable and easy to set up.

In this guide, you’ll discover everything you need to know when choosing a small window air conditioner. You’ll also find out what size ac you need for your windows as well as things you need to consider when making a purchase.

Keep in mind, the size of the window air conditioner you choose determines how cool your room will be. Under-powered or over-powered ac units are not efficient, so make sure you have the right dimensions for your room.

10 Best Air Conditioner For Small Window Opening Reviews

What Size Window Air Conditioner Do I Need?

Investing in a window air conditioner is the best way to beat the heat without your energy bills skyrocketing. These units are also affordable, readily available in various cooling capacities to accommodate rooms of all sizes.

Choosing the right size window ac determines whether your cooling needs will be met or not. Size doesn’t always refer to the physical dimensions of the unit but rather the BTUs (cooling capacity).

However, it’s common to find that small air conditioners have low BTUs while big units have high BTUs.

The most important factor you have to consider when choosing a window air conditioner is the size of your room, which will help you calculate the cooling capacity.

So, if you have a large room, you’ll require high BTUs, which equals greater cooling capacity. On the other hand, a small room requires a low BTU, which equals low cooling capacity. 

Keep in mind that bigger isn’t always better. An air conditioner too large will cool more quickly without removing enough humidity, leaving the room with a damp, clammy feeling. A small unit, on the other hand, will have to work twice as much to cool the room effectively. We have also reviewed the best window air conditioners for large rooms.

So, what is the best way to find the right BTUs? First, you have to measure your space to calculate square feet. Then you can use the table below to determine the correct cooling capacity. Some air conditioners also include the BTUs and the recommended room size.

However, some factors can allow you to increase the BTUs needed for your room. They include;

  • Ceiling Height: The estimates above assume that you have the traditional 8-foot ceilings. If your ceiling height is higher than 8 feet, consider increasing your BTU levels.
  • Sunlight: If your room is facing the sun, increase your BTUs by 10 percent.
  • Shade: If your room is shaded for most of the day, decrease your BTUs by 10 percent.
  • Number of Occupants: If you have more than two people occupying the room, add 600 BTUs of cooling power for each person.
  • Kitchen: If you are installing your window AC in a kitchen, increase the BTU level by 4,000

Features to Consider When Choosing the Best Air Conditioner for Small Window Opening

  • Energy Efficiency: Air conditioners must be highly energy-efficient to allow you to stay cool without worrying about your energy bills. Look for units with a high Energy Efficiency Ratio because the higher the EER, the most efficient the unit is.
  • Dehumidifier: This is a great feature to look for if you live in a humid environment. A dehumidifier removes excess moisture from the air, preventing the growth of allergens such as dust mites, mold, and mildew.
  • Cooling and Fan Speed Adjustment: You want to be able to customize your AC to meet your cooling needs. AC with multiple cooling speeds allows you to get the room to cool faster when necessary. The fan speed delivers a gentle circulation of air without wasting energy cooling when it’s not needed.
  • Noiseless Operation: Some of these units are designed to operate without creating noise. Although they aren’t as powerful, they are best suited for smaller rooms that require silence, such as the bedroom or a home office.
  • Thermostat: This feature allows you to control the output temperature of the air conditioner. The budget window air conditioners tend to have a traditional mechanical thermostat. It’s in the form of a dial that you can rotate to set the temperature of the room.
  • Automatic Timer: The automatic timer feature makes it possible to program when the air conditioning unit turns itself on/off. This feature helps you save money. The budget models allow you to set intervals, while the newer models have advanced timers that allow pre-programming the unit beforehand.
  • Auto Restart: The auto-restart function in a window air conditioner is useful in case of power failure. The unit saves your previous settings and restarts the unit automatically when the power comes back.
  • Air Filter: The air filter collects the impurities from the air and provides clean and fresh air. While most of these filters need replacement from time to time, some of them are washable and can be used again.

How to Clean a Window Air Conditioner Without Removing It

It’s essential that you carry out regular and proper maintenance of your air conditioning unit, as it can otherwise lead to a breakdown. You can clean the air conditioner by yourself and don’t need to hire a professional each time, except for when you require service.

If you want the unit to work efficiently, clean it once a week. This will help you save your time cleaning, and money spent on expert inspection when you get it done after a long time. Also, it’ll ensure that the unit stays in good shape throughout its lifetime.

Before you get started on the cleaning process, here’s everything that you’ll need,

  • Tap water
  • Bucket of water
  • Detergent or soap solution
  • Hydrogen peroxide
  • Spray bottle
  • Dry towel

Once you’ve gathered the tools, here’s how you should go about it.

For daily cleaning, turn off the unit first. Fill the spray bottle with hydrogen peroxide and gently spray the intake area. Ensure you don’t inhale the fumes and wash your hands properly later. 

If you notice that the filter isn’t clear, you need to deep clean the unit. Remove the filter and spray the unit further. You can also use a wet towel to clean the filter and the unit. Before you operate the device, put the filter back in place, and let it dry out completely.

In the case of monthly cleaning, the unit would require thorough cleaning. After you’ve switched off the system, remove the front panel so you can easily slide out the air filter. 

You can either place the filter under a running tap or clean it by dipping the towel into a soapy or detergent solution. Hot water can also be used to clean the filter and the front panel. 

But if you notice that the air filter is covered in a layer of dirt, the best solution is to clean it with a vacuum hose. Set aside the filter to dry or wipe it with a dry towel before you place it back into its position. 

If the front panel or the filter is damaged, you need to change it with a new one to ensure that the unit functions properly.

Although we wouldn’t advise you to clean your air conditioner seasonally, you can do it when it requires a deep cleaning. 

After making sure that power is disconnected, remove the unit case first. Clean it with a hot water detergent solution, and with the help of a wet towel, clean the dirt. 

Next, remove the filter and clean it with a wet towel or by merely dipping it in a water bucket. With the help of a soft brush, clear out the dust from the aluminum fins. Spray the fins and coils until they’re clean. Dry out the unit before placing the parts back into place. If any component is worn out, get it replaced.

Following these steps will help you clean the unit without having to remove it from its place and ensure that it continues to provide fresh and clean air.

Top 10 Best Air Conditioner For Small Window Opening 2021

1. Frigidaire FFRA0511R1 5000 BTU Window-Mounted Mini-Compact Air Conditioner

No products found.

The Frigidaire FFRA0511R1E Window Air Conditioner has 5000 BTU of cooling capacity that is enough to cool a room up to 150 square feet. Other customers who have bought the product reported that it could handle up to 200 square feet of space. It also has a dehumidification power of up to 1.1 pints per hour, something that you won’t find from other ac at this price range.

Before buying and installing this unit, make sure your window has a minimum height of 13 inches and a width of 23 inches to 36 inches. It comes with a window mounting kit for easy installation and uses the standard 115V electrical outlet.

In addition to its small size, this window ac has two fan speeds, two cooling speeds, and two-way air direction that can be manually programmed using the rotary controls. So that means you won’t get a remote control.

One of the ways to cut down on air conditioner maintenance costs is to choose a washable filter. That is something you get when buying this ac. The filter is also easy to clean, you can wash or vacuum it periodically.

The low power start-up, quiet operation, and effortless restart are some other features worth mentioning because they make the ac user-friendly and convenient.


  • The unit minimizes the extra usage of electricity with its low-power startup feature.
  • The air conditioner cools and dehumidifies the room at the same time.
  • It offers a number of settings for fans and speeds.


  • This air conditioner doesn’t come with an energy-saving mode.
  • The unit doesn’t have the automatic restart feature.

2.Frigidaire FFRE0533S1 Window-Mounted Mini-Compact Air Conditioner

Frigidaire 5,000 115V Window-Mounted Mini-Compact...
  • 2016 energy star: 12.2 energy efficiency Ratio (EER)
  • 5,000 BTU mini-compact air Conditioner for window-mounted installation, Dehumidification up to 1.1 pints per hour
  • Quickly cools a room up to 150 sq. Ft, Cabinet Height: 12", Cabinet Depth (w/ Front): 15-1/4", Cabinet Depth: 13"
  • Safety Certification: UL/CUL (SA11087), ENERGY STAR Certified: Yes, UL Listed: Yes
  • Low power start-up and operation conserves energy and saves you money
  • Window Width: 23" - 36", Window Height: 13"

If you are looking for the freedom to adjust the temperature and other settings of your air conditioner using a remote control, then this is an excellent option than Frigidaire FFRA0511R1E. So, if that is something you consider important to you, choose Frigidaire FFRE0533S1.

The Frigidaire FFRE0533S1 has a 5000 BTU cooling power and can keep a room up to 150 square feet comfortable. It can also dehumidify up to 1.1 pints per hour.

Since it is available at an extremely affordable price and high 12.2 energy efficiency Ratio, it’s the perfect choice for energy-efficient comfort all summer long and even in spring and fall. You can also conserve energy and save money by taking advantage of the low-power startup and operation.

Like Frigidaire FFRA0511R1EE, this unit is easy to install thanks to the included installation materials. It fits in windows 23 to 36 inches that are at least 13 inches in height.

Apart from all the features it has, it’s also UL/CUL and ENERGY STAR Certified. That means it’s efficient and safe for household use.


  • Affordable and energy-efficient
  • Automatic restart and 24-hour timer option.
  • Window mounting kit for easy installation.
  • The removable air filter provides clean and fresh air.
  • UL and CUL certified


  • There have been a few complaints of fan rattling, creating a loud operating environment.

3. LG 6000 BTU Window Air Conditioner

LG 6,000 BTU Window Air Conditioner, 115V, Cools...
  • Window Air Conditioner with Low Noise Performance: This ac window unit operates at sound levels as low as 52dB (in low mode) eliminating unnecessary noise; Work without distraction and get a good night's sleep with this quiet window unit
  • Multiple Fan Speeds: 3 cooling and fan speeds allow you to customize your cooling; Effortlessly adjust the window unit ac air flow to suit your needs
  • Maximum Usability: This window unit ac includes an easy to use digital control panel and remote control; 2-way air deflection gives you ultimate flexibility; Filter light reminder, window installation kit, and a slide-out, washable filter are included for your convenience
  • Auto Restart: After a power failure, Auto Restart will automatically turn the small window ac unit back on when power is restored
  • Cools Rooms up to 250 Square Feet: LW6017R is ideal for cooling medium rooms (10' X 25'); With 250 square feet cooling coverage, keep your bedroom or office comfortably cool with this small room air conditioner

 The LG LW6017R window air conditioner has 6000 BTU of cooling power, which is enough to keep a room up to 260 square feet comfortable during the sweltering summer. Apart from air conditioning, this small AC has a dehumidification feature that removes up to 1.8 pints of water per hour.

One of the advantages of choosing LG LW6017R is the auto-restart function that is helpful in case of a power outage. Also, it has 3 different cooling and fan speeds that allow you to adjust the settings according to your preference. The two-way airflow and auto cooling help to keep the room cool and free from any excess moisture.

The 24-hour on/off timer and the energy-saving features are additional benefits as they help you save energy by allowing you to turn on the ac when it’s needed the most. You can also take advantage of the electronic touch controls and the remote to adjust the settings and modes.

If you’re the kind of person that forgets to clean your air conditioner, then worry no more because this unit is equipped with a filter alarm function that notifies you when it needs cleaning.

While LG LW6017R is a reliable and awesome unit to add to your home, it’s slightly noisy, so you want to keep that in mind if you decide to buy it.


  • The air conditioning unit comes with an energy-saving mode.
  • It has an indicator light that tells you when the filter needs to be cleaned.
  • The timer in the air conditioner allows you to set it according to your specific cooling requirements. 


  • The air conditioner can only be used in rooms that are up to 260 square feet in size.
  • The cooling unit can be a bit noisy and distracting.

4. Friedrich Chill 6000 BTU Window Air Conditioner

Friedrich Chill CP06G10B window air conditioner comes with 6000 BTU of cooling capacity, which is sufficient to cool down a room up to 250 square feet. It also features an inbuilt dehumidifier capable of removing up to 1.8 pints per hour.

This Energy Star Certified AC also has an efficient energy-saving mode that’ll help you bring down your energy bills by maintaining the set temperature. The unit utilizes a 24-hour digital timer that enables you to program when to turn on and off ahead of time.

It also has an auto-restart feature that resets the unit to the previous setting when the power comes back. This model comes with a digital display and remote control that allows easy adjustment of the various features.

This is another small air conditioner that can be installed on a window or wall thanks to the slide-out chassis. The installation kit is included, and the power cord can run either left or right out of the side of the unit front


  • The air conditioner has an auto-restart function and uses a 24-hour thermostat.
  • The window cooling unit features an efficient energy-saving mode.
  • It comes with a digital display and digital remote control.


  • Only fit to be used in a room 250 square feet in size.
  • The installation kit doesn’t contain all the required pieces and tools.

5. Emerson Quite Kool 6000 BTU Window Air Conditioner

Emerson Quiet Kool 6,000 BTU 115V SMART Window Air...
  • Quiet Cooling: This 6,000 BTU window air conditioner efficiently cools up to 150 to 250 sq. ft. At 52dB, this unit is among the quietest in the industry, making it ideal for bedrooms, living rooms, apartments, and any other environment
  • Smart Voice Control with Alexa and Google: This Wi-fi enabled, smart through the wall air conditioner pairs easily with both Amazon Alexa, through the Smart Life skill, and Google Home, by enabling Smart Life in the Home Control section; Additional Wi-Fi controls via the HE Smart app on your smartphone or tablet supplement these voice controls
  • Programmable Timer and Sleep Mode: Integrated 24-hour timer can be set via on-board controls or remote control; Intelligent sleep mode takes it one step further by slowly adjusting the temperature and fan speed to keep you comfortable overnight while saving you energy and money
  • Exclusive 1-2-5 Warranty: Your Emerson Quiet Kool Wi-fi enabled air conditioner comes with an industry-exclusive 1-2-5 warranty that covers 1 year of labor, 2 years of parts, and 5 years on the compressor; Buy and use with confidence
  • Split Air Exhaust Vents: 2 air exhaust vents (instead of 1) combine with 3 fan speeds to give you 8-way flexibility to direct the flow of cold air where you want it when you want it

The Emerson Quiet Kool SMART window air conditioner offers 6000 BTU of cooling capacity, which is designed for a room up to 250 square feet in size. It also removes excess moisture up to 1.5 pints per hour from the air to provide a more comfortable environment.

This unit is quite easy to install and comes with a remote control to adjust several features, including a 24-hour on/off timer, electronic controls with 3 speeds, and flexible cooling options. With the Wi-Fi and voice control options enabled, you can monitor and control the unit with your smartphone.

This model is Energy Star compliant with a 12.1 energy efficiency ratio. In addition to that, the low voltage startup helps to lower your electricity bills further. The auto-restart feature is convenient in a power failure. The air filter comes with an indicator light and is easy to wash and reuse.

However, a lot of customers have complained that this air conditioner is quite noisy.


  • Low power startup and energy-efficient features save energy.
  • Wi-Fi and voice control features.
  • The unit has washable air filters with a filter indicator 


  • There have been several complaints about the unit being noisy.

6. Whirlpool Energy Star 6000 BTU Window-Mounted Air Conditioner

Whirlpool 6,000 BTU 115V Window Air Conditioner &...
  • Powerful Cooling: The 6,000 BTU window air conditioner is powerful enough to cool rooms up to 250 square feet with 1.6 pints per hour of dehumidification
  • Functionality: Electronic control panel with digital display and 3 cooling speeds, eco mode, sleep mode, and programmable 24 hour on/off timer
  • Easy Installation: Comes with a quick and effective window mounting kit that allows for easy installation in windows with minimum window height of 14.5"
  • Replaceable Filter: Clean Alert indicates when air filters should be replaced or removed and washed for convenient maintenance
  • Auto Restart: After a power failure, the unit automatically restarts when power is restored

The Whirlpool Energy Star 6,000 BTU 115V Window-Mounted Air Conditioner is another affordable and simple-to-use unit that efficiently cools a room up to 250 square feet. A the same time, it can also dehumidify, removing 1.58 pints of moisture per hour.

Like many other Energy Star Certified air conditioners, it has a high energy efficiency ratio of 12.2. It also features an eco mode that helps to conserve energy and lower your electricity bills. It also offers sleep mode, 3 cooling speeds, and 8-way directional air louvers for efficient cooling.

Most of the smallest window air conditioners have manual controls. However, Whirlpool WHAW061BW has an upgraded remote control with an LCD display, allowing you to adjust the temperature or change other settings without leaving your favorite spot. It also has a timer that can be set from 30 minutes to 24 hours in advance.

Maintenance is another crucial factor when choosing an ac. Whirlpool has done a great job because they have included a removable filter that is easy to clean. This is the only maintenance required for this model.

While Whirlpool WHAW061BW can be the perfect addition for many homes, we noticed that many customers complained about the rattling noise it produces.


  • Offers 3 cooling speeds and 8-way directional control for efficient cooling.
  • Features a 24-hour programmable on/off timer and auto-restart function.
  • Includes an easy-to-remove washable air filter.
  • The system comes with a window installation kit for easy installation.


  • Complains that the unit becomes unreliable after a short period of time.
  • Users claimed that the fan makes rattling noises.

7. Keystone KSTAW05B Window-Mounted Air Conditioner

No products found.

Keystone KSTAW05B is another affordable air conditioner for small window openings that uses a 5-15P GFCI outlet plug for vertical windows with at least 13 inches, horizontal windows, or between 23 to 36 inches wide for double-hung windows.

It is a great option for staying comfortable and cool during the summer since it’s energy-efficient with an EER of 12.2 and a cooling capacity of 5,000 BTUs for rooms between 100 – 150 square feet. It also features a dehumidifier that removes 1.3 pints of moisture per hour.

Besides the high EER, it also offers an energy saver mode that is intended to help you save money. It, therefore, will cycle for two minutes at 10-minute intervals to maintain the set temperature. Other modes that you may want to put to use include a sleep mode, fan-only mode, and follow-me mode.

The unit comes with electronic controls with an LED display and a temperature sensing LCD remote control, allowing easy control of temperature. It also has an auto-restart feature and an easy-clean, mesh filter with an indicator light. All this comes along with a window installation kit.


  • The unit features electronic controls with an LED display and temperature sensing LCD remote control.
  • The window air conditioner has a mesh easy-to-clean air filter with a check filter alert.
  • The air conditioner comes with a window installation kit.


  • Installation isn’t easy – it requires at least two people for installation for safety due to the positioning and weight of the unit.
  • Some people claimed that the unit is extremely loud and noisy.

8. ARCTIC Wind 2016 Energy Star 6,000 BTU Window Air Conditioner

Arctic Wind 2016 Energy Star 11,500 Window Air...
  • 2016 energy star (12 EER)
  • 11,500 BTU air Conditioner for window-mounted installation
  • Cools a room up to 500 sq. Ft
  • Digital control panel with LED display
  • Adjustable temperature control with 24-hour timer and energy saver function

ARCTIC Wind 2016 Energy Star 6,000 BTU Window Air Conditioner delivers effective indoor cooling with excellent efficiency. That is because it has a high Energy Efficiency Ratio (EER) of 12.1 than most ordinary air conditioners in its price range.

This energy-efficient window AC offers 6,000 BTU to keep a room up to 260 square feet comfortable during the summer. While some models in this list might be energy-certified, ARCTIC Wind 2016 Energy Star 6,000 BTU Window Air Conditioner features a convenient Energy Saver mode that maintains a comfortable room temperature while conserving electricity.

It comes complete with a window mounting kit and uses a standard 115-volt electrical outlet. After installation, you can use the remote control or the digital control panel to adjust the settings which you can check from the LED display. You also can use the adjustable temperature control together with the 24-hour timer to program the unit to start or stop your home at specific times of the day.

Overall, this is a great window air conditioner with great features, affordable and efficient.


  • This air conditioning unit comes with a digital control panel with an LED display.
  • In case of a power outage, the auto-restart features save your settings.
  • The air conditioner includes a complete window mounting kit.
  • The unit comes with a washable mesh air filter with a ‘clean filter indicator light.


  • A lot of customers have complained that the air conditioning unit is very noisy.

9. MIDEA MAW06R1BWT Window Air Conditioner

Midea 6,000 BTU EasyCool Window Air Conditioner,...
  • 3 IN 1 COMFORT - The Midea EasyCool Window Air Conditioner unit has three modes to help your house, apartment, office, or room be as comfortable as possible. It can cool a space up to 250 sq. ft. quickly, circulate air with its 3-speed fan, or reduce humidity utilizing the dehumidifier mode.Controller type:Remote Control.Air Flow efficiency:168.82 CFM.Core material : Copper..Frequency : 60 hz
  • ENERGY EFFICIENT - The EasyCool window air conditioner is Energy Star certified to help save you money throughout the year. There are also multiple custom settings to help you be even more energy-efficient like Eco mode and an EasyTimer feature to program a schedule that fits your needs.
  • QUIET & EASY TO USE - This window AC unit is quieter than a household refrigerator. The intuitive LED display and remote control (batteries included) allow easy setting of time, temperature, and mode from across the room. The removable and reusable air filter protects your family and living space from dust and pet hairs.
  • EASY INSTALLATION - Install easily in your home or apartment's existing window frame (23"-36"x14"). All mounting accessories are included. A screwdriver is required (but not included) for installation. For some window frames, pilot holes are recommended before installing screws. Installation instructions are simple and setting it up is a breeze.
  • WORLDWIDE LEADER - Midea is the world’s #1 air treatment brand with a motto to help make customers feel at home with each of their products. As a testament to our dedication to quality and our customers, we offer one-year parts and labor warranty on this product.

If you are looking for more than just an air conditioner, then this is the unit to buy. It delivers powerful cooling performance to rooms up to 250 square feet while at the same time dehumidifying and circulating cool air in the room using the fan mode to maintain a comfortable temperature.

MIDEA MAW06R1BWT offers unique EcoSave functionality that gives you more control over your cooling bills by alternating between compressor cycles and fan cycles to reduce energy consumption. Moreover, the 24-hour programmable timer allows you to set the AC to turn on or off in advance.

This ac is designed for the standard wooden window frame, not an aluminum-framed window. All the installation hardware is included, plus it’s easy to install, and you don’t have to modify your existing window frame.

Whereas other AC units at this price only come with manual controls, this one has a remote control and a clear LED display on the front panel that allows you to adjust your settings quickly.


  • Easy to install
  • Multiple operations modes
  • simple operation
  • Programmable timer
  • Eco-mode
  • Quiet


  • While it’s easy to install, it’s not a 1-person job
  • No instructions for either use or installation


A window-mounted air conditioner offers several different features and specifications, which can be quite confusing and make it a difficult task for a buyer to decide on a single product. But we’ve provided you with a list of the best air conditioner for small window opening

With our guide on how to pick the right size and what features to look for, we’re sure you’ll be able to choose which product you’re going to purchase that meets all your requirements.