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largest btu window air conditioner

Largest Window Air Conditioners With The Highest BTU Ratings

The demand for a window mounted air conditioner has always been somewhat on the greater side due to their affordability and utility.

There are many available from very small units to quality silent models all built to match the situation.

Most window units vary from approximately 6,000-25,000 BTU's, that is the cooling capacity that a unit has.

Larger units include 10,000-25,000 BTU's or more.

One thing to remember while looking for a large window AC unit is 115 volt systems max out around 12,000 BTU.

Anything bigger will usually require a 230-volt outlet, which most rooms won't have 220-240 volts is typically only used by electric stoves, clothes driers, and electric water heaters.

Below are our picks for the most reliable large window air conditioning systems.

As always, be sure to read the reviews on Amazon or elsewhere to make sure a unit is a fantastic fit for you.

What's In This Buying Guide

Our Picks For Best Big Window Air Conditioning Units

highest btu window air conditioner

Frigidaire is a top A/C manufacture that has many units available in all sizes and shapes.

An FFRA282WAE model is a huge unit at 28,000 BTU, that's rated to cool a distance up to 1,900 square feet.

It will need a 230-volt socket to work and won't run from a typical 115-volt plug.

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Koldfront makes many Window A/C units from small to big.

The model WAC10002WCO is a 10,000 BTU unit and operates from a typical 115-volt outlet.

It's an excellent standard unit with 3 speeds, remote control, and many other features.

There are larger units, but most will operate from 230 volts.

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LG is just another famous air conditioner company with several units out there.

They have sizes ranging from 6,000-18,000 BTU.

The new LG Units also come with or without WiFi. That's a wonderful feature.

The LG LW1516ER 15,000 BTU unit is about as large as they come for 110-115 volts standard home outlet

largest btu window air conditioner

Friedrich Chill has many window A/C units ranging from 5200-24,000 BTU.

The 24,000 BTU unit is rated to cool a space up-to 1400 Square Feet.

It's also well built and one of those quieter window components available.

biggest window air conditioner

This black and decker model isn't the standard window unit and built for portability.

It works by pumping out heat a 5-inch hose that can be readily placed in a window.

It also can heat in the winter. That's a bonus when it gets chilly.

With 14,000 BTUs of cooling power, it's one of the higher-rated A/C units, which will run from a 110-120 volt socket.

The bottom has wheels to roll it around for portability, for example, keeping away until needed.

This makes it perfect in many scenarios, such as apartments or other rental units when a unit isn't permanent.

Things to Consider When Purchasing a Large Window Air Conditioner

Window air conditioners are made to cool one or several rooms that contain windows that can be used to vent hot air outside.

There are many things to consider when buying a larger window air conditioner, but these are the top 5:

1. Cooling Capacity

Cooling capacity should always be your primary concern when purchasing a window AC.

Cooling power is listed in British Thermal Units, or BTUs, per hour.

Always choose a unit that has a BTU rating that matches the size (square footage) of the room(s) you want to cool.

A window AC with too little BTU for a large room will operate continuously to try and cool the space, and in the process will consume far too much energy.

A unit that has too much BTU for a small room will not cool and dehumidify your area thoroughly, leaving your room with uncomfortable cold and hot pockets.

To find your perfect cooling capacity, first compute the size of the space you need to be cooled in square feet. Then match it to a BTU - floorspace table.

2. Installation

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Most window air conditioning models are made to fit inside a regular double-hung window.

But many models today can be installed to vent hot air outside through a wall using special hardware. This is a useful option if your window sizes are too small or too big or if you do not have vertical sash windows.

In a Window

Measure the dimensions of the window frame just, focus particularly to the width. Then, start looking for the minimum and maximum window width measurements listed in the AC's specifications.

Do not worry if your model does not stretch to fit your window frame correctly.

Most window air conditioners include installation kits that provide expandable  side drapes to seal off the extra space on either side of a window opening.

In the Wall

For wall installation, first ensure the model you want can use this setup and then buy the appropriate installation kit.

After that, create a note of the finished wall opening measurements recorded in the item's specifications.  If needed, consult with a specialist.

Some window ACs can also be placed through a wall, so make sure you shop carefully.

When fully installed – whether in a window or through a wall – your window AC will sit inside the opening, together with the warm air vent system facing outside and the heating system is facing indoors.

Additionally, many window air conditioners feature a slide-out chassis and a rugged mounting sleeve which stabilize and secure the device while providing you with easy access to it for maintenance.

All window air conditioners today come with detailed, easy-to-follow directions for setup.

3. Electrical Requirements

Almost all window air conditioners work on 115, 125 or 220-volt circuits today.

115-125 Volts: Air conditioners with cooling capacities under 15,000 BTUs usually operate on a standard residential (115 to 125-volt) circuit.

220 Volts: Window air conditioners with cooling capacities over 15,000 BTUs usually operate on 220-volt circuits. Installation of these can be more involved. You may need to install new electrical wiring or seek an electrician to help you with these.

A window unit’s electrical requirements – including amps, voltage, and watts – will be listed in its specifications.  Additionally, the right plug face type may be pictured or listed by its NEMA (National Electrical Manufacturers Association) classification.

4. Energy Efficiency

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Generally, the best window air conditioners are more economical than central air conditioners. They cost less to purchase and, if sized properly are more economical to operate over the long term.

To judge a unit's energy efficiency, look for two attributes:

Energy Star Rated

Energy Star Rated air conditioners use about 10 percent less energy than other models, which helps you save money on operating costs.

Most states provide rebates for customers who buy an Energy Star model. So definitely look for this one.

EER (Energy Efficiency Ratio)

This specification lets you know how many BTUs of cooling is provided for every watt of electricity consumed by it.

Use this as a rule of thumb: the higher the EER, the more efficient the AC.

According to the U.S. Department of Energy, you should shop for a room air conditioner with an EER of 10.0 for the best energy efficiency and cost-savings.

Friedrich window ACs are famous for their high EERs and Energy Star-qualified operation.

5. Maintenance

Window air conditioners need periodic maintenance to keep them in prime condition.

They are vulnerable to outside debris and dirt, which can collect inside or on the back especially after a big storm.

Moreover, particles and dust will collect on the air conditioner's air filter.

If left untreated, these items will eventually decrease the effectiveness of your air conditioner.

To ensure long-lasting operation, clean your air conditioner thoroughly at least once each year.

A window AC with a slide-out chassis makes this really handy because all you've got to do is slide the unit out to get to it.

Many air filters are washable with mild detergent and water.

For special maintenance tips for your version, refer to your owner's manual.

For protection from insects, some room ACs, such as the Friedrich Kuhl Series, are furnished with mosquito traps that let condensation flow outward without allowing insects indoors.


If you've got a large space to cool this summer, a large window air conditioner is a fantastic option.  They are more economical than central AC units and cost much less to install.

Most 115-volt units will max-out at a BTU rating of 10,000-12,000 BTU, enough for perhaps two rooms - while larger systems will require 230 volts. If there is no 230-volt socket in your room, one can be installed by an electrician but increases the price tag.

Also, make sure you measure your window’s opening to make sure that a unit will match.

In addition to window ACs, you may want to consider buying a portable air conditioner. Both work equally well when installed properly. Portable units pump heat out through large air hose, usually 5-7 inches wide, which can be pushed through a window or a wall.