By Tony Carrick | Updated Sep 30, 2021 3:46 PM

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While window air conditioning units are a fine option for cooling a room, they require sacrificing a window and the view that comes with it, along with some of its aesthetics. The best through-the-wall air conditioner offers a viable alternative. These air conditioning units function similarly to window air conditioners, but they fit into a hole in the wall, preserving the view and aesthetics of the room’s windows.

A through-the-wall air conditioner can produce up to 15,000 BTUs (British Thermal Units), making this type of air conditioner suitable for cooling rooms up to 700 square feet. Some models also include heating elements that supplement a home’s main heat source. This guide examines the crucial factors to consider when shopping for the best through-the-wall air conditioner and lists some of the best options on the market.

While selecting the right through-the-wall air conditioner to suit the size of the room is crucial, other factors are also important, including energy efficiency, operating modes, and whether the unit has a heating function option. Below, learn more about these and other attributes.

Through-the-wall air conditioners are ideal for rooms that remain warmer than other parts of the home or that aren’t served by a central air conditioner’s ductwork. This could include a garage, a bedroom, or a bonus room.

While it’s possible to mount a wall air conditioner anywhere on an exterior wall, most units are mounted close to the floor so they are less conspicuous and don’t detract from a room’s aesthetics. When choosing a location, make sure there is enough space around the installation location on the exterior side to allow the air conditioner to draw air into the compressor.

Through-the-wall air conditioners are installed into a sleeve that fits into a hole in the wall. In order for the air conditioner to fit properly, the depth of the sleeve should be equal to or greater than the thickness of the wall. Most walls are about 5 to 7 inches thick, depending on the type of siding used on the home. Most air conditioner sleeves fit walls that are 8 inches thick or less.

Matching the size of the air conditioning unit to the size of the room is crucial to selecting the right model. If the air conditioner is too small, it won’t be able to cool the space to the desired temperature. Purchasing an air conditioner that’s too large is overkill. The air conditioner will be more expensive than a smaller unit and cost more to run.

The best way to determine the right size air conditioning unit is by matching the square footage in the room to the air conditioner’s energy output, which is measured in BTUs. Most wall air conditioners range in output between 8,000 and 18,000 BTUs. An 8,000-BTU air conditioner can cool up to 350 square feet, while an 18,000-BTU model cools up to 1,000 square feet.

While many through-the-wall air conditioners use a standard 115-volt outlet, some high-output models require a 230-volt connection, which can require special wiring.

The more cooling power an air conditioner produces, the more electricity it uses. An 18,000-BTU air conditioner uses more than twice the amount of electricity of an 8,000-BTU air conditioner. To compare the energy efficiency of two wall air conditioners, calculate each unit’s energy efficiency ratio by dividing its watts by its BTUs to determine its Energy Efficiency Rating (EER). The higher the EER, the more efficient the air conditioner is. Most through-the-wall air conditioners have an EER rating between 9 and 11. Many manufacturers advertise the EER of their air conditioners.

Air conditioning units with Energy Star ratings must have an EER of at least 12. While Energy Star-rated units tend to cost more up front, they can quickly make up for that difference in energy savings. An Energy Star-rated wall air conditioner uses 15 to 30 percent less electricity than models not Energy-Star rated, even with the same BTU output, making them cheaper to run.

Many through-the-wall air conditioners also offer a heat mode through a small built-in heating element. Air conditioners with heater functions that plug into a standard 115-volt outlet, as opposed to a 220-volt outlet, can produce around 5,100 BTUs of heat, enough for 144 square feet, while air conditioners that use a 230-volt connection can produce around 10,600 BTUs of heat, which is enough to heat a 500-square-foot space.

Keep in mind that the heating function is meant to supplement a furnace or provide a touch of warmth on a cool day. Through-the-wall air conditioners are not meant to serve as a main source of heat.

Many through-the-wall air conditioners have additional features that purify the air in a room, adjust the airflow, or allow the user to customize its operation. A dehumidifier mode uses the air conditioner to reduce the humidity inside a room by running the fan on low mode and intermittently turning on the condenser. A fan-only mode circulates air throughout the room without using the condenser to cool the air, while a sleep mode runs the air conditioner at a quieter noise level while also slowly increasing the temperature through the night to accommodate for the natural decline in body temperature that happens during sleep.

Most wall air conditioners also have programmable 24-hour timers that automatically shut the air conditioner off after a set amount of time. Other features include louvers that allow the user to adjust the direction of the air and air filters that clean the air by removing airborne contaminants such as pollen, dust, and mold spores.

Like window air conditioners, through-the-wall air conditioners include a compressor that creates the cool air and an air handler that blows air into the room using a large fan. This dual design tends to be noisier than central air conditioners, which feature a compressor that is outside the home and an air handler that is typically tucked away in an attic, or a ductless air conditioner, which has a compressor that is on the exterior home.

Since the air compressor is in close proximity to the living space, through-the-wall air conditioners are noisier, producing about 50 decibels, which is similar to light traffic or moderate rainfall. Some through-the-wall air conditioners feature quiet operation settings, which can drop the decibel level into the 30s. Keep in mind that when an air conditioner operates in quiet mode, it runs the compressor at a lower level, producing less cold air.

Measuring around 24 inches wide, 20 inches high and 15 inches deep, a through-the-wall air conditioner is a sizable appliance. While these air conditioners are typically installed in an unobtrusive location, such as below a window, they are still a very visible feature in a room. So as not to detract from a room’s aesthetics, most models are white with understated features that include simple adjustable louvers that can direct airflow and a slatted vent that covers the filter and air intake. Some through-the-wall air conditioners include a trim kit that allows the user to create a more finished look between the appliance and the wall.

The list below narrows the field of through-the-wall air conditioners to some of the best models on the market by coverage area. These air conditioners range from 8,000 BTU models for small rooms to 15,000 BTU behemoths for large spaces. They feature multiple operating modes and efficient Energy Star ratings.

With its 10,000-BTU output, this through-the-wall air conditioner from Koldfront can cool up to 400 square feet, making it ideal for bedrooms, offices, and other small rooms. A convenient remote control allows the user to control all of the air conditioner’s settings, adjust temperature, and turn the unit on and off from across the room.

Despite its smaller capacity, this is a versatile air conditioner with numerous settings and functions, including a dehumidifier setting that reduces the humidity in the room, a sleep mode for quieter operation, and a 24-hour timer. This air conditioner measures 20.4 inches wide and 14.5 inches high, and it uses a 115-volt outlet for power, eliminating the need for complicated hard wiring.

Many through-the-wall air conditioners on the market can crank out enough cold air to cool a large space. What sets this model from Frigidaire apart is its ability to do it efficiently. With its 12,000-BTU energy output, this air conditioner can cool up to 550 square feet efficiently enough to earn an Energy Star rating, making it one of the most economical options for cooling a larger space.

It also includes other useful add-ons such as a thermostat in the remote control (a must for evenly cooling larger spaces) and standard features such as a programmable timer, multiple fan speeds, a sleep mode, and an energy-saver mode. At 24 inches wide, 20 inches high, and 14.5 inches deep, Frigidaire’s through-the-wall air conditioner is similar in size to other models.

Features that improve the accuracy of temperature readings and high energy efficiency make this through-the-wall air conditioner a worthy pick for smaller rooms. One downside of window-mount and wall air conditioners is the challenge they face evenly cooling a room when the thermostat is located near the unit’s output—the coolest place in the room. Keystone solves this issue by enabling users to place the thermostat in areas not in close proximity to the air conditioner.

This useful feature plus an Energy Star rating makes it worth the additional cost—this model is more expensive than other 8,000-BTU models. Similar to other through-the-wall air conditioners, this air conditioner has multiple fan speeds and offers useful additional features such as a programmable auto-shutoff, a sleep mode, and an energy-saver mode. At 24 inches wide, 14.5 inches high, and 20 inches deep, this through-the-wall air conditioner is average in size. This air conditioner plugs into a 115-volt outlet.

With a BTU output that’s notably higher than most wall air conditioners and an ability to function as either a through-the-wall air conditioner or as a window air conditioner, this is one of the most versatile and powerful air conditioners on the market. It boasts a staggering 15,100-BTU output, which is enough to cool a room up to 700 square feet.

This makes it ideal for cooling homes with open floor plans or even an unfinished garage. An Energy Star rating helps keep energy usage down, while industry-standard features such as an energy-saver mode, a sleep mode, and a programmable 24-hour timer add useful functionality. Keystone also thoughtfully includes a “follow-me” feature with its remote. This allows the air conditioner to sense the temperature in the room through the remote to more evenly cool a room. This air conditioner plugs into a 115-volt outlet.

The size of the area being cooled will determine which through-the-wall air conditioner works for your space, and the Koldfront Air Conditioner is a top choice to get the job done. It’s well suited for most rooms and cools efficiently.

The advantage of through-the-wall air conditioners is that you won’t sacrifice a window to get the cool air that’s needed. These recommendations were selected based on their BTU capacity to cool rooms of various sizes, whether it’s a bedroom, living area, or even a shed. Additionally, each unit has an energy efficiency rating to help users reduce their energy costs without sacrificing comfort.

These units are easy to install and come with adequate instructions for installation and operation. We also selected products that include a remote control to make it much easier to control from anywhere in the room. Our favorite models operate with several fan speeds and automatically reduce output when the desired temperature is reached. Some units have programmable timers for users who prefer maximum control.

If you’re wondering how wall air conditioners differ from window air conditioners or which model to choose for your home, then read on for answers to some of the most commonly asked questions about these appliances.

Window and wall air conditioners are two distinctly different types of air conditioners. A window air conditioner fits inside a window of the home, while a through-the-wall air conditioner fits into a hole in an exterior wall. Both types of air conditioners draw air in from the outside and cool it before blowing it into the room.

The best way to choose an air conditioner is by measuring the square footage of the room and finding an air conditioner that is built to cool that amount of space.

Most through-the-wall air conditioners plug into a standard 115-volt outlet. However, larger models require more power and hence a 220-volt connection.

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