Welcome to our Window AC buying guide and reviews of the best window units.
Introduction to the Guide
This expert window air conditioner guide is the most comprehensive of its kind, but we’ve also made it easy to find what you’re looking for.
There are two ways to use the window AC guide:
This guide concludes with several “Best of the Best” lists – like Most Efficient models, Models with Premium Features, Smartest window units, Best Values, Window ACs with heat elements, Casement window units and more.
A handful of manufacturers dominate the market, and we have completed Window AC Brand Review for each one. They allow you to compare brands like LG, GE, Frigidaire and Friedrich head to head in terms of efficiency, cost, models and features and all other important comparisons.
Window AC FAQs – Understanding the Basics
Let’s start with an overview of window air conditioner basics, so you’ll have a clear idea whether a window unit will meet your needs.
1. How does a window AC work?
As the name implies, a window unit fits in the space created when you open the sash of a window. Most window air conditioners are designed for single-hung/double-hung windows, but the major brands now make window units for casement/sliding windows.
Some homeowners frame a permanent sleeve through a wall to accommodate the AC. When installed in a wall, the AC doesn’t obstruct a window. This installation is known as a built-in unit.
A window AC uses refrigerant to absorb heat inside your home and disperse it outside. That’s why the back of the air conditioner looks like a radiator. The maximized surface space allows for faster dissipation of the heat.
Inside air is pulled over a coil in the front of the AC. The heat from the air is captured by refrigerant in the coil. Taking heat from the air makes it cooler, and the cooled air is blown into the room.
2. Does a window air conditioner remove humidity?
Yes it does. As the coil in the front of the window unit removes heat, it gets very cold – almost freezing cold. As you know, moisture in the air condenses on cold things like a glass of ice water. Moisture condenses on the coil and channeled to a tube and drained outside. When inside air is very humid, water can be seen steadily dripping out the back of a window air conditioner.
3. What sizes are available – and how do the sizes compare with central ACs?
Window air conditioners range from 6,000 BTUs to about 28,000 BTUs. Size is also referred to as capacity.
The number of BTUs (British thermal units) is the amount of heat the unit can transfer per hour.
Standard split system central ACs start at 18,000 BTUs. The largest are 60,000 BTU models.
Mini split ACs are made in capacities from 6,000 to 60,000 BTUs.
4. Can it cool more than one room?
Window units are mostly used to cool a single room or area. They can cool multiple rooms if the home has an open floor plan.
5. How much power does a window air conditioner use?
Most units under 15,000 BTU are 110-120 volts. Models larger than 15,000 BTU are 220-240 volts.
6. Are window air conditioners as efficient as central ACs?
Window ACs have EER ratings of about 9 EER to 12.4 EER. EER is explained below, but the higher the EER (energy efficiency ratio), the more efficient the unit.
Standard split system ACs range from about 11 EER to more than 16 EER.
Mini split (ductless) ACs have EER ratings from about 10 to 20.
7. Is a window AC the same as a room AC?
In short, a window air conditioner is one kind of room air conditioners.
Window AC vs Central AC: When Window Units are a Better Choice
Let’s start with the other side of the coin – when central air conditioning is preferred. Then we’ll look at ideal situations for a window air conditioner.
When central AC is better: If you’re building a home where hot weather or warm, humid weather is typical in summer, then central air conditioning is a better choice. This is especially true if you have more than $5K in the budget for a system that will meet your home’s cooling requirements. In these situations, central air conditioning will produce lower monthly utility bills than 3-5 window units running in various rooms or areas of your home. Central AC will probably keep your home more comfortable too – better temperature balance and lower humidity.
When a window unit is better: There are times when a window air conditioner is better or at least an acceptable alternative to central AC.
Here are the most common reasons to choose a window AC:
Window AC Pros and Cons
Exploring window AC advantages and disadvantages is another way to compare your home cooling options.
Like all air conditioner types, window units are becoming more efficient as technology advances.
While window ACs are not as efficient as central air conditioning, they can still help you keep energy costs in check when used wisely.
Efficiency is how well an air conditioner uses energy to move heat from inside to outside. It’s like gas mileage.
Efficiency ratings: There are two measurements of window air conditioner efficiency, CEER and EER. They are closely related. We’ll compare them with SEER too, a measurement used with central air conditioners.
- EER is energy efficiency rating: It is the measurement of the unit’s efficiency when the air temperature is 95 degrees F. If you enjoy the technical side of things, “EER values are typically measured under laboratory conditions of 95°F condenser-entering air and 80°F drybulb and 67°F wetbulb evaporator-entering air,” according to the American Council for an Energy-Efficient Economy.
- CEER is combined energy efficiency rating. This is the new standard for room air conditioners. It measures EER with the addition of how much power the unit uses when plugged in and turned on but not running.
- The CEER is typically slightly below the EER rating. For example, the 12,000 BTU Frigidaire FFRE1233UE has an EER rating of 12.1 and a CEER of 12.
- SEER is seasonal energy efficiency rating. Used for central ACs, SEER measures the unit’s efficiency over an entire season. SEER is usually slightly higher than EER/CEER because it is measured under a wider range of temperatures. An AC will be more efficient when air is 80 degrees than if it is 95 degrees. SEER is also influenced by climate. For comparison to the Frigidaire model, the Bryant 180CNV has a SEER rating of 18 and an EER rating of 13.
Window AC efficiency compared to central and mini-split ac: Window units are not as efficient as split and mini split central ACs.
However, that doesn’t necessarily mean that it will cost more to run one or two window air conditioners compared with a central air conditioner. It depends on the size of your home, the efficiency ratings of the models and how many window units you use.
In warm-to-hot climates, central air conditioning will reduce annual electric bills compared to window units because the AC will get heavy use.
In cool climates, using a window air conditioner to cool one or two rooms will reduce energy use compared with cooling an entire home with a central AC.
Is Buying the Most Efficient Window AC Worth the Money
There’s a simple equation for determining the answer to this question:
Divide the extra cost of the more efficient unit by the annual energy savings.
Let’s break that down. The two units must be the same size, such as 10,000 BTU. Follow these steps:
1. Determine the extra cost of the more efficient unit: Subtract the lower price from the higher price to determine how much more expensive the more efficient unit is.
2. Determine the annual energy cost savings of the more efficient AC: Every appliance comes with a yellow Energy Guide that shows its efficiency and average cost of running it. The Energy Guide is posted on the box, if you’re shopping at the store. If shopping online, a link to the Energy Guide is often included in the information.
3. Subtract the lower cost from the higher cost. This is the annual cost savings you’ll enjoy with the more efficient AC.
4. Divide the higher price of the more efficient unit by the annual energy cost savings. The answer to that equation is the number of years it will take you to recover the extra cost through lower energy costs.
Analysis of 10,000 BTU window air conditioners:
- Frigidaire 10.9 CEER: MSRP $269 / Annual Energy Use $89
- Haier 11.2 CEER: MSRP $329 / Annual Energy Use $79
The Haier unit costs $60 more and uses $10 less energy per year. The equation is an easy one.
60/10 = 6 years
You would recover the extra $60 spent on the Haier in just 6 years. From there, you would save yourself $10 every year in lower energy bills.
Are these “huge” savings? No, but if you plan to keep the AC, it makes sense in this case to buy the more efficient Haier unit. Besides saving money, you’ll have a smaller carbon footprint for greener air conditioning.
Energy Star air conditioners: Units certified by Energy Star are at least 10% more efficient than the average efficiency of all window ACs. Every year, that average rises, and so does the CEER rating needed to qualify as an Energy Star product. Currently, the threshold for Energy Star ranges from 9.9 to 12.1 depending on the size of the unit and other variables. Energy Star criteria are listed on this page.
Features to Consider
Window units range from very basic On/Off ACs with a fan speed knobs to feature-rich air conditioners. Here are some of the options to consider when shopping.
Of course, the better the features, the higher the average cost of the unit will be.
Digital controls: Most units have digital controls, but the most affordable ACs have knobs.
Benefit: Digital control allows you to set the temperature more precisely. It’s also necessary for the timer, sleep mode and other features.
Timer and programmable start: These features allow you to plan when the AC turns on and off and for how long it runs.
Benefit: Using these features allows you to cycle the AC on and off in moderately warm weather to save energy. Also, using the programmable features is the best way to reduce energy use when you’re not at home. Rather than leave the unit on all day, program the AC to turn on 30-60 minutes before you plan to arrive.
Wi-fi: Window units with wi-fi connectivity allow you to control them remotely with an app.
Benefit: It’s the easiest way to reduce energy use. If you forget to turn the unit off when you leave home, it can be done with the app. Then, use wi-fi to turn it back on before you get home. There’s no wasted cooling.
Sleep mode, econ mode, energy saver mode: These are all names for the similar features.
Benefit: When you choose the mode, the AC will allow temperatures to slowly rise over several hours.
Inverter or standard compressor: Standard compressors run on one or two speeds (High or Low and High). Inverter-type compressors speed up and slow down in very small increments. They run longer during each cycle, but they cool the space more gently and evenly without “blasts” of cold air.
Benefit: The result is that an AC with an inverter compressor uses less energy and cools more comfortably. However, it will cost more than a same-size AC with a standard compressor.
Fans speeds and fan-only mode: Window units have 2-4 fan speeds. Some have fan-only mode.
Benefit: Climate control within the room or space is easier with more fan speeds. Choose a low speed if you’re sitting near the AC, for example, and a higher speed when you need cool air to reach the far side of the room. Fan-only mode allows the AC to continue to dehumidify and filter the air even when the compressor isn’t running.
Auto restart after outage: With this feature, the unit will turn on and return to your settings when power is restored.
Benefit: If you aren’t there during the outage, you can return home to a cooler, less humid house.
Remote: Adjust the AC temperature or other settings from across the room or from another room.
Fresh air option: Indoor air becomes polluted when the house is closed up tight and the AC is running. Some window air conditioners have a vent setting that pulls in fresh outside air to cool and dehumidify. The downside is that it takes more energy, since the outside air is warm and humid.
Benefit: That option can be chosen for an hour or two to freshen the indoor air.
Clean filter alert: A light or digital notification lets you know the filter is dirty.
Benefit: A dirty filter makes the AC work hard, so it is less efficient. Cleaning it alleviates the problem and also allows for cleaner indoor air.
Ionizer: An ionizer is an air cleaner that captures pollutants through an electronic charge.
Benefit: A unit with an ionic filter can produce cleaner air.
Since 2006, most new window air conditioners have R-410A refrigerant. R-410A replaced ozone-depleting R22 refrigerant.
Now, R32 is available. Here’s how they compare:
Units with R32 cost slightly more, but have about 1/3 the environmental impact of R410A units. Here’s a Data Sheet on R32 from the non-profit Eneref Institute.
What Size Window AC do I Need
Choosing the proper size window unit for your needs is essential for these reasons:
“Just right” comfort: You want an AC to adequately cool the space without overpowering it. A unit that is too large will cycle on and off too often, so it won’t remove much humidity. The result will be a cool, clammy indoor climate.
Energy efficiency: An air conditioner is most efficient when it has to run much of the time to keep a room cool. In other words, it is more efficient to use an 8,000 BTU unit that runs 75% of the time during hot weather than a 12,000 BTU unit that runs 50% of the time.
Here is a summary of its buying guidance for room air conditioners:
1. Determine the square footage of the room or space to be served by the AC
2. Use the Table to match the square footage to be cooled with the AC size required (30 to 40 BTUs per square foot)
Area To Be Cooled (square feet)
Capacity Needed (BTUs per hour)
100 up to 150
150 up to 250
250 up to 300
300 up to 350
350 up to 400
400 up to 450
450 up to 550
550 up to 700
700 up to 1,000
1,000 up to 1,200
1,200 up to 1,400
1,400 up to 1,500
1,500 up to 2,000
2,000 up to 2,500
3. Adjust for these room features:
Here’s a sample for a 15x20 living room:
1. The room is 300 square feet. According to the Energy Star requires an AC with 8,000 BTU capacity.
2. The room is on the west side of the house and not shaded, so gets very warm on sunny afternoons: Add 800 BTUs (10%)
3. The room is often occupied by 2-4 people: Add 600 to 1,800 BTUs.
4. Total BTUs of cooling required: 10,000 to 11,200 BTUs.
Most brands make ACs in increments of 2,000 BTUs.
- A 10,000 BTU unit would probably be just right, though the room might be slightly warm on a very warm afternoon when 3+ people are in it.
- A 12,000 BTU unit might be OK on a hot day with several people in the room. But on a cloudy day with just one or two people in the room, it might slightly over-cool and under-dehumidify the room, adding a damp chill to the air.
If you live in a moderate or cool climate, we’d recommend the 10,000 BTU model.
If you live in a warm or hot climate, especially with high humidity, the 12,000 BTU window air conditioner would be the better choice.
The guide to sizing a room air conditioner is also available in this video from Energy star.
How to Buy the Right Window AC
Here are a few window AC buying tips.
Size: Determine the capacity of the AC you need, so you can limit your shopping to window air conditioners that will run efficiently and comfortably in your home.
Efficiency: Here’s a simple tip. The hotter and longer your summers are, the more money you’ll save with a more efficient AC.
Use: If the AC is the main source of cooling, then follow the guideline that warmer climate = higher efficiency AC. If it is supplemental air conditioning for rooms not fully cooled by central AC and is only used on the warmest days, then choosing a less efficient unit is fine.
Features: A good principle is to pay for features you’ll use, but don’t waste money on those you won’t. Wi-fi is a good example. It’s a great way to reduce AC use and still have your home comfortable when you are there. However, if you have a very consistent schedule, then a timer is enough. If the unit is in a room that you only use part of the day, then you might not need any specialized features. A very basic AC might be sufficient.
Tips to Reduce Energy Cost
Buying an efficient window AC is just the first step. Here are ways to make your AC and entire home more efficient:
- Use the timer to program on/off times rather than leaving the window unit on when you’re not in the room.
- Shade sunny windows. Thermal shades are available that reduce the transfer of heat into the room. Less heat means the AC doesn’t work as hard.
- Install an awning above the AC window. This is a permanent and more effective way to shade a sunny window.
- Add weather stripping around the AC. Stop drafts from allowing cool air to escape and warm air to enter the room.
- Size the AC properly.
- Use a ceiling fan or floor fan to move air. Moving air feels cooler than stagnant air.
- Add insulation to the attic. Energy experts make this their top way to cut down on energy costs and make your home more comfortable. Adequate attic insulation (R-38 to R-60 depending on your climate) is the best way to stop summer heat from penetrating through your roof, making your home hot and your AC work harder. It keeps in heat in winter too.
- Use bathroom vent fans and a kitchen vent when cooking. Removing moisture from the air makes air feel more comfortable in warm months.
- Consider a whole-house fan. The fan is designed to exchange the warm air in your home for cooler nighttime air. These fans cost far less than central air conditioning. When the house is cooled off at night, it will stay cooler longer during the day, so less AC will be required.
In this section, we first give an introduction to the top 6 window AC brands. We have completed full reviews for each. Then, you will find a list of the top individual models in important categories like efficiency, quietest window ACs and the features they offer.
Top Window Air Conditioner Brands Reviews
While there are dozens of window AC brands, many are untested – or tested and proven to be unreliable.
A handful of window air conditioner brands have been making dependable models for many years, so are worth considering when you make your purchase. And there is one innovative new brand many are excited about. While untested, Noria window ACs will be game changers. The brand has big financial backing, so there’s hope Noria window units will live up to the hype.
Here are the best window air conditioner brands:
LG Window Air Conditioners
LG is known for innovation and good-looking window ACs. It makes more than 20 models, so you have a good selection of size and feature options.
LG makes mini split air conditioners and has imported some mini split technology into a few of its advanced window units. The most notable is inverter-driven compressors that produce quiet, efficient and comfortable cooling. LG is one of the first manufacturers to use R32 in its window units. The refrigerant doesn’t deplete the ozone and has a lower global warming potential than R410A.
Most LG models include useful features like 24-hour timers, remotes, multi-speed fans and airflow in 3 or 4 directions. Wi-fi ACs and window units with supplemental electric heaters are available.
LG doesn’t make window units for casement and sliding/gliding windows. Check our Best Casement Window Air Conditioner post if you need that.
The lineup from Frigidaire includes more than 60 window units. There’s a good mix of basic, knob-controlled models that are more affordable and digital ACs with advanced features and performance. Frigidaire also makes a few models for casement windows. All models use R410A refrigerant.
A few models also have ionizers to electronically clean the air. Wi-fi, remotes, timers and other supplemental heat are among the other features available.
Our Frigidaire Window Air Conditioner buying guide is a good place to research your options. It sorts out the 60+ models into efficiency, cost, features and more.
Friedrich window air conditioners are among the most technologically advanced available, but are also somewhat expensive. The brand also stands out for making models with capacity up to 36,000 BTUs, larger than most. Two lines, Kühl and Chill, are made in cooling-only and cool + heat models. Friedrich calls the heating models “heat pumps,” but the heat is produced by electric space heaters, not by traditional heat pump technology.
The Kühl line includes commercial-grade components for proven durability, though at a higher cost. The Chill line is more affordable, but in general, Friedrich is a high-end brand.
Our comprehensive Friedrich Window AC buying guide explains your options, their features, costs and more. There are tips for sizing a window air conditioner and choosing the best fit for your room, apartment or home.
General Electric has scaled back its window air conditioner lineup to just a handful of models. All of them are feature-rich, so you won’t find affordable GE window units. All models have electric heaters, not true heat pumps. They include timers, remotes, multiple-speed fans and 4-way air louvers that allow you to direct airflow to all parts of the room.
Size options are limited to 8K, 12K, 18K and 28K BTUs.
See our GE Window Air Conditioner Reviews for a breakdown of the models, their features and GE window AC prices.
There are nearly 20 Haier window air conditioners to consider. They range from 5,000 BTUs to 24,000 BTUs. Most other brands produce larger window air conditioners. Most Haier window units are Energy Star certified. A few Haier models are affordably priced knob-controlled units.
The Haier window AC lineup offers most of the features you’d expect: 24-hour timers with delayed start, multiple fan speeds and directional airflow. There are no models with supplemental heat. Some Haier window air conditioners have wi-fi connectivity. The refrigerant used in all models is R410A.
Our Haier Window Air Conditioner Guide includes much more information about models, their efficiency and features and Haier window AC prices.
The Noria Kapsul is scheduled for release in January 2020.
The unit has a low 7” profile, so won’t obscure your view out the window. They are Bluetooth and wi-fi connected for convenient monitoring and control from anywhere. The Kapsul works with Amazon Alexa, Google Home and the nest thermostat.
Fresh air mode for times when the outside air is cooler than inside air. The mode allows you to freshen indoor air that gets polluted in tightly built and insulated homes when windows and doors remain closed.
Information about sizes, efficiency and features isn’t complete, but it looks like the first unit introduced will be the 5,000 BTU W5 model shown in this video. We will update our Kapsul/Noria Window Air Conditioner Guide when the ACs are released and we can review them.
Best Window Air Conditioners in 2020
Here are the top models in the most important categories to consumers.
The Most Efficient Window AC
In most window unit series, the smaller the unit is, the higher the CEER rating will be. The following models have the highest CEER ratings for the entire series.
- LG LW1817IVSM Series have CEER ratings of 14.5 to 14.7 due to their inverter-type compressors. This includes units up to 22,000 BTU.
- Haier QHM window air conditioners have CEER ratings of 10.3 to 12.1.
- Frigidaire FGRQ, FGRC and FFRE Series also include small units with a CEER rating of 12.1.
Quietest Window AC
If you’re placing the unit in a bedroom, then you’re looking for a quiet window air conditioner.
These are the quietest window ACs:
- The Frigidaire FGRQ window air conditioners are available in 6,000 and 8,000 BTU units with multiple fan speeds. The 6K model runs as quiet as 41 decibels. The 8K runs from 44 to 51 decibels.
- The Haier ESAQ 6,000 BTU window air conditioner is an office and bedroom AC that runs at 43 decibels, one of the quietest ACs available.
- The LG LW 17IVSM Series are larger units that run very quietly. They have an inverter style compressor that delivers more or less cooling based on the room temperature. Its noise range is 44 to 58 decibels. Models 14K, 18K and 22K BTUs are available.
Premium – Best Features Window AC
These window air conditioners are feature-rich with most or all of the following:
- 24-hour timers with delay
- Sleep mode for energy savings
- Remote controllers
- Multispeed fans
- Fan-only mode
- Slide-out chassis for easier maintenance
- 4-way airflow
Some advanced features like wi-fi and heat pump technology are covered in additional categories below.
- The Frigidaire FFRA Series is the top in this category. In addition to the features listed, it has supplemental heat, an air ionizer, an alert when the filter needs cleaning and auto restart that starts the AC after a power outage and applies the same settings as when power was lost.
- The GE AEE Series have supplemental heat and an electronic thermostat that is more accurate than a thermistor.
- The LG LW 16HR Series and Friedrich Chill have supplemental heating. The Friedrich Kühl S and Y window air conditioners are commercial-grade, expensive ACs with either supplemental electric heat or heat pump technology.
Greenest Window AC
If you want to reduce energy use and carbon emissions, these ecofriendly window air conditioners will help.
R32 is the most environmentally friendly refrigerant available in window units. It doesn’t deplete ozone and has a lower global warming potential than the R410A that is used in most window ACs. LG LW 17IVSM, LW 17ERSM and LW 16ER units use R32.
High efficiency is another way to reduce environmental impact. We list the most efficient window air conditioners above.
Most Compact/Smallest Window AC
The Kapsul Air W5 is designed to be the most compact window air conditioner. It is just over 7” tall, so your view out the window isn’t totally obscured.
Other small, compact units in the 6,000 to 8,000 BTU range are the LG LW18ER, Friedrich Chill CP and Haier QHM models.
Best Vertical Window AC
The Frigidaire FFRS ACs are the only window air conditioners among the top brands that are made for casement/sliding/gliding windows. 8,000 and 10,000 BTU units are available.
Best Value Window AC
These are affordable window units that deliver good quality. Most have manual knobs instead of digital controls. If you want cheap cooling, they are the answer.
- The Haier QHV is the most affordable window air conditioner from the top brands. It’s a 5,000 BTU model.
- The Frigidaire FFRA manual-control models are low-cost window air conditioners in 4 models from 5,000 to 10,000 BTUs.
- The LG LW 18ER models in 6,000 and 8,200 BTU models are larger and still affordable.
Best Window AC with Heat Pump
Air conditioners are heat movers. They cool a room by capturing heat inside and moving it outside.
A true heat pump reverses this process. It collects heat outside and moves it inside. Heat pump heating uses 2/3 less energy than electric space heating.
The Friedrich Kühl Y Series are the only heat pumps made by the top 6 window air conditioner brands.
Best Window AC with Space Heating
Electric resistance heating uses more energy than a heat pump, but it can be economical as supplemental or occasional heat. For example, if you have a bedroom that is distant from the furnace, it might not get enough heat.
A well-insulated, sealed window air conditioner can supplement the heat from the furnace.
All four GE window air conditioner models have supplemental heating elements. They are also included in the Friedrich Chill EP and Kühl E Series, LG LW 16HR and the Frigidaire FFRH window units.