A large room (about 400-700 sq. ft.) needs a window air conditioner that has high BTU output, energy efficiency, and performance.
This article is a review of the best window-mounted AC units to use in large rooms and a comparison of their cooling capacity, noise, special features such as smart connectivity, and so on.
The table below is a brief comparison of our best choices, and then we will discuss them in detail and provide a buying guide to assist you in selecting the best unit to fit your room.
| Window AC Unit | Cooling Capacity | Room Size | Key Features |
|---|---|---|---|
| LG 14,000 BTU Dual Inverter Smart Window AC | 14,000 BTU (115V) | Up to 700–800 sq. ft. | Dual inverter compressor, ultra-quiet ~44 dB, Wi-Fi (ThinQ app), Energy Star |
| Midea U-Shaped Inverter Window AC 12,000 BTU | 12,000 BTU (115V) | Up to 550 sq. ft. | U-shaped design (open window flexibility), super quiet 42 dB, Wi-Fi (Alexa/Google), Energy Star Most Efficient |
| GE Smart Window Air Conditioner 14,000 BTU | 14,000 BTU (115V) | Up to 700 sq. ft. | Traditional compressor, Wi-Fi (SmartHQ app), Energy Star, 3 fan speeds, remote control |
| Friedrich Chill Premier Inverter 18,000 BTU | 18,000 BTU (230V) | Up to 1,000 sq. ft. | Precision inverter (42 dB quiet mode), Wi-Fi (FriedrichGo app), slide-out chassis, heavy-duty build |
| Keystone Budget Window AC 18,000 BTU | 18,000 BTU (230V) | Up to 1,000 sq. ft. | High output cooling, dehumidifier mode, 3 fan speeds, remote control (No Wi-Fi) |
| TCL Energy Star Window AC 15,000 BTU | 15,000 BTU (115V) | Up to 700 sq. ft. | Digital thermostat, Energy Star efficiency, multi-directional airflow, sleep mode, remote |
#1 LG 14,000 BTU Dual Inverter Smart Window AC – Best Overall
LG 14,000 BTU Dual Inverter window air conditioner is one of the best air conditioners to use in a large room because it is very powerful and highly efficient. This Energy Star model employs the Dual Inverter Compressor technology of LG to adjust the cooling speed, thus saving up to 25 percent of energy consumption and delivering ultra-stable temperatures.
It has a cooling capacity of 14k BTUs, and is comfortable on rooms of about 600-700 sq. ft. (LG rates it to about ~800 sq. ft.).
The most impressive thing is the silence of this AC, it can work as low as ~44 decibels on its LoDecibelTM quiet mode, which makes it one of the quietest in its category (almost background noise level). This is a massive advantage to bedrooms or living rooms where a loud AC would be distractive.
The LG Dual Inverter has a powerful airflow even though it operates quietly and can cool down a hot large room within a short period of time. According to users, it makes you cool and comfortable even during the heatwaves, and the compressor does not have to roar on and off all the time.
The LG is a smart unit and it supports Wi-Fi connectivity through the LG ThinQ app. You can manage power, temperature, modes and fan speeds via your phone, or even voice control with Alexa/Google Assistant. This brings a lot of convenience e.g. you can switch on the AC before you reach home so that the room is cooled.
Other features are 24-hour programmable timer, energy saver mode, auto restart and full-function remote control. It also possesses a washable mesh filter that has a clean-filter alert to ensure maximum performance.
- Large cooling capacity in large rooms; Dual Inverter technology saves power and keeps the room at a constant temperature.
- Very low noise (44 dB) – can be used in bedrooms and living rooms.
- App and voice-controlled (ThinQ, Alexa, Google) Wi-Fi enabled with easy remote control.
- Energy Star (CEER ~14.7) – extremely efficient in its size.
- Unit weight (~112 lbs); it might need two individuals to install it safely.
- High-end pricing– the smart and advanced inverter is more expensive than the basic ones.
- Needs a special 115V plug (uses ~12A); check that your circuit is up to it.
#2 Midea U-Shaped Inverter Window AC 12,000 BTU – Ultra-Quiet Efficiency
When the most important factors are quiet operation and high efficiency, the Midea 12,000 BTU U-Shaped Smart Inverter will be a brilliant choice. It is unique in its U-shaped design whereby the compressor section is placed outside the window and the interior section is mostly isolated by the window pane. This arrangement drastically secludes noise.
Actually, the Midea U is nine times quieter than conventional ACs and it can go as low as 42 dBA which is almost as silent as a library. The users are usually amazed at the fact that they can sleep or watch TV with this AC on.
Although it has a lower 12k BTU rating, the Midea is cooled very well by its inverter technology and efficient design, and is able to cool medium-large rooms (up to ~550 sq. ft.). It was also among the first window ACs to receive the Energy Star award of the most efficient, with more than 35 percent energy savings compared to standard AC units.
The inverter compressor is smooth in adjusting the output, thus you do not experience the rough on/off cycling, it keeps the cooling steady and saves on electricity. The air is very powerful such that you can feel the cold air even at a distance of 20 feet.
The other major advantage of the U-shaped Midea is that you can literally open and close the window even with the unit in place and bring fresh air in when you want to. It is supplied with a special quick-snap bracket to make it easy to support (installation is not the same but also easy, usually a two-person job).
This model also has Wi-Fi; it is possible to change settings remotely via the Midea Air application or voice control (Alexa/Google Assistant) and even program schedules. It is ideal to keep the comfort at a maximum with noise and energy consumption at a minimum.
- Super-silent operation – U-shape design muffles compressor noise (42 dB on low), amazing in noise-sensitive places.
- Outstanding efficiency – inverter technology + Energy Star Most Efficient 2021 (35 percent less energy consumption) can reduce electric bills.
- Enables partial use of windows: special shape enables you to open the window to get fresh air without taking out the AC.
- App and voice Wi-Fi smart control; physical remote as well. Very handy and advanced (cooling, fan-only, dehumidify modes, etc.).
- It is slightly more complicated than a typical window AC (need to mount the support bracket and place the unit carefully in the window opening). Two individuals suggested to be installed.
- Fits only standard single/double-hung windows (not casement or sliding windows). Measure your windows- requires approximately 14″ of vertical clearance.
- 12k BTU cooling capacity should be fine in most large rooms but extremely large rooms or rooms with direct sun exposure may require a higher BTU unit (Midea does not yet offer a U-shaped above 12k).
#3 GE 14,000 BTU Smart Window Air Conditioner – Reliable Wi-Fi Cooling
GE 14,000 BTU Smart window AC is a more classic design large-room unit that provides powerful cooling and easy Wi-Fi connectivity. This 115V air conditioner has a capacity of cooling rooms of up to 700 sq. ft., which means it can be used in dens, large bedrooms or living rooms.
It has a normal rotary compressor (not inverter), hence will turn on/off to keep the temperature. GE has designed this model to provide quick and strong cooling- users report that it can cool a large area within a short time even during hot days.
As an Energy Star model, the GE 14k is not as efficient as the inverter units (approximately 11.3 CEER), but it is decent. It has three cooling speeds and three fan-only speeds and an Eco mode to save energy.
The built-in Wi-Fi (GE SmartHQ app integration) is one of the major selling points. You will be able to control and monitor the AC regardless of the location, e.g. turn it on using a smartphone before you get home, or change the settings without leaving the chair. It also has voice control using Alexa and Google Assistant. This intelligent feature brings in much convenience and aids in the management of energy consumption by setting on/off timings. Naturally, there is a simple remote control too.
It is easy to install as this GE unit has a slide-out chassis sleeve, which makes it easier to place in the window (and also can be installed through-the-wall in case you want to do so). Remember it is a heavy unit (~100+ lbs), so the safest way to do it is to install the chassis and then slide in the guts.
Noise wise, it will be slightly louder than the inverter models, on high it can go to the mid 60 decibel range, which is audible but normal on a big AC. At low/medium it is less noisy (low 50s dB) and that is sufficient in most cases but light sleepers may want to use an inverter AC at night. On the whole, this GE is a perfect combination of good cooling, intelligent functions, and brand reputation.
- High 14k BTU cooling power – cools large rooms (up to ~700 sq. ft.) in a short time and keeps the room cool in the hottest weather.
- Built-in Wi-Fi and SmartHQ app to control and schedule completely remotely; compatible with Alexa/Google Assistant to use voice commands.
- Energy Star certified – energy efficient, non-inverter model, with such features as Eco Mode and programmable timer to consume less power.
- Heavy duty slide-out chassis construction to facilitate easier mounting and possible wall mounting. Comes with complete installation kit and adjustable side panels.
- The noise level is more than inverter models. It may be audible on max cool (fan and compressor hum ~63-67 dB) and this may annoy noise-sensitive individuals at night.
- It is very heavy at ~105 lbs, so it should be installed with proper support bracket and at least two people.
- The fact that the compressor cycles on/off implies that you may experience minor temperature fluctuations and hear the compressor turn on. The fan also turns off in Eco mode, which is energy-saving but others might want to have the fan running all the time.
#4 Friedrich Chill Premier Inverter 18,000 BTU – Premium Quiet Power
The Friedrich Chill Premier 18,000 BTU window AC is a beast of an air conditioner in case you have an extra-large room or one that requires the best of the best performance. Friedrich is a commercial grade brand and this inverter driven unit meets that reputation with excellent cooling capacity and library quiet operation given the size of the unit.
It has 18k BTUs, which is more than enough to cover 700+ sq. ft. (up to approximately 1000 sq. ft.), which is why it is a good choice to cover large living areas, open-concept rooms, or even tiny apartments. Note that this model needs a 230V outlet (usual on units larger than ~15k BTU).
The Friedrich Chill Premier adjusts the speed of its compressor in a smooth manner due to the Precision Inverter technology. That provides two large advantages: very good energy efficiency (SEER ~13, very high in a window AC) and low noise.
It is able to operate as quietly as ~42 dB on cooling mode low fan which is very quiet considering it is a large unit. It is even quieter and less rough sounding than other ACs that the owners have used even at higher fan speeds. The QuietMaster design by Friedrich has heavy insulation and a stiffened sheet metal case to minimize vibration and transmission of noise.
What it adds up to is that you have a lot of cooling and not a lot of racket, which is a big plus in large areas where you may entertain or watch television.
This Chill Premier series AC is also a full smart-enabled one. You can remotely control the settings of the unit and schedule it using the FriedrichGo mobile app (or by connecting with Amazon Alexa/Google Home). It is well endowed with features such as Money Saver (energy saver) mode, 24-hour timer, sleep mode, and an auto swing 8-way airflow that distributes air better.
It has a slide-out chassis, which helps with installation (you mount the sleeve and then slide in the guts) as well as allows optional through-wall install in case you need it. Remember that the unit itself weighs about 120 lbs and thus installation will definitely need support and probably professional or several individuals.
- Strong 18,000 BTU cooling capacity – cools huge rooms or several adjacent rooms with ease. Perfect when 14k units are not enough.
- Inverter technology + high quality construction for very quiet operation (as little as 42 dB) and efficient operation (frequently will run at low power after the set temp has been reached).
- Voice control ready, Wi-Fi app control ready; it also has a sleek touchpad and remote. Many comfort features (8-way vent direction, fan speeds, etc.).
- Long-lasting construction – Friedrich units are constructed to be used in heavy-duty applications and they are likely to last long provided they are maintained.
- Needs 230V power supply – you need a 230/208V receptacle (and circuit) to be available. This is typical of high-BTU ACs but a critical factor.
- Extremely heavy and big chassis (fits a window width ~27″ to 42″). Strong mounting bracket or professional installation strongly recommended.
- High price tag- it is among the high-end window ACs because of the inverter technology and the quality of construction. But the investment is worth it when you really need its capabilities as far as the performance and longevity are concerned.
#5 Keystone 18,000 BTU Window AC – Budget Big Cooling (230V)
In case you want high BTUs at a lower price, the Keystone 18,000 BTU Window Air Conditioner is a good choice that provides powerful cooling at an affordable cost. The 230V model has sufficient power to cool a large room of up to approximately 1000 sq. ft., and is thus appropriate to cool an entire floor, or a large space.
Neither an inverter nor a smart AC, it is rather a more traditional window unit that is aimed at the basics: cooling, dehumidifying, and easy control. You end up with a dependable cold air to a big area with few bells and whistles, and usually at a cheaper price than the high-end brands.
The Keystone has a remote control, three cooling speeds, three fan speeds and an energy-saver mode. It is also a dehumidifier, which draws up to approximately 3.8 pints of moisture an hour out of the air to make the room feel more comfortable.
Its 18k BTU compressor has been reported to be able to cool a large room quickly and it is this kind of power that you want on a hot summer day. It has a variable 4-way air direction louvers to assist in directing the cold air where it is required.
This unit is 230V/15A and will need the proper outlet (NEMA 6-15 style plug). The energy efficiency is not bad (it complies with DOE standards with about 11+ EER). It will run at a high speed, so it will be somewhat audible, but the sound level should be somewhere in the middle of 60 dB at full volume, which is quite common with this size AC.
The Keystone is a good option, though it does not have Wi-Fi or fancy integration, but it has a lot of cooling power and does not cost a fortune. It is a favorite choice of big garages, living rooms, or open apartments.
A strong window will be needed to install it and probably a support bracket (it weighs approximately 110 lbs). Among the benefits is the fact that the chassis is slide-out and this can make mounting easier. On the whole, this model provides the basic objective of cooling a big space efficiently and is an excellent low-cost workhorse AC.
- Good bang-per-buck BTU rating – a low cost method of obtaining 18,000 BTUs of cooling, which is appropriate in ~700-1000 sq. ft. areas.
- Easy to use, easy to understand remote; has cooling, fan only and dehumidify modes. Flexibility is given by multi-speed fan and adjustable vent.
- Takes out a lot of moisture in the air of the room, useful in muggy weather.
- Heavy duty and durable performance as observed by most of the owners – it blows out very cold air and can last long in beating the heat.
- No smart functions or Wi-Fi, it is completely manual/remote control. This is not a disadvantage (unless you do not require connectivity).
- 230V need- make sure you have the correct outlet; otherwise, you may have to hire an electrician to put one in.
- Noise is comparable to normal big ACs (not very quiet). The compressor and high fan will be audible on max cool so it might not be suitable in a bedroom where you are a light sleeper.
- The design is functional – it is not the most modern-looking unit (plain boxy design), but it is functional where it counts.
#6 TCL 15,000 BTU Window Air Conditioner – Energy-Star Large Room AC
Another good choice to cool large rooms of about 600-700 sq. ft. is the 15,000 BTU window air conditioner of TCL (a brand that specializes in electronics and TVs). It is Energy Star certified, which implies that it complies with or surpasses the requirements of low power usage, which is impressive given that it is a 15k BTU model.
It has several fan speeds and cooling modes so that you can set the output to your comfort. It is an excellent unit to use in big master bedrooms, living rooms or any open space that a smaller AC will not cover.
The TCL has a digital thermostat and a clear display, and it has a full-function remote control, so you can change the temperature and settings even when you are at the other side of the room. It has a 24-hour programmable timer to set on/off times and it even has a sleep mode that slowly changes the temperature to save energy at night and still keep you comfortable.
Airflow wise it has 8-way directional vents (so you can blow air left/right and up/down as required). It has 15,000 BTUs and can cool a hot room very fast, people have noted that it has a strong cooling ability and can cover large rooms where other smaller units could not.
A unit of this size is normally installed. It is suitable to windows of approximately 26-36 inches wide (see the minimum/maximum window width) and it needs a solid window frame because the weight of the unit is approximately ~100 lbs. It is provided with a window mounting kit.
It is a 115V model, which consumes approximately 12-13 amps, thus can be connected to a standard household outlet (ideally on a dedicated circuit). The noise is normal: not too loud when the fan is low, and a constant whoosh when it is high.
Although this TCL lacks the Wi-Fi connectivity on the entry-level model, it compensates with a solid performance and a relatively lower price than some of the high-end rivals. It is a powerful large-room air conditioner that is concentrating on the main task of cooling.
- High-performance 15k BTU cooling – can cool even large rooms (up to 700 sq. ft.) and cool them down fast.
- Energy Star certified – has environmental friendly features such as programmable timer and sleep mode to save energy.
- Easy to use controls: digital panel with thermostat, and remote control. Easy to set controls and temperature.
- Various fan/cool speeds and 8-way air direction will help to get rid of hot spots in the room. Auto-restart also (restarts with previous settings in case of power outage).
- This model has no smart/Wi-Fi capabilities (TCL does have other smart AC models, but this one can only be controlled by remote or onboard controls).
- It is heavy like other large units and it might need a support bracket to be safe. Install with caution.
- Other users mention that the maximum fan speed is loud, which is not unusual of a large AC, but keep in mind that you may want to get a quieter inverter model, in case you need a super-quiet AC.
- The remote does not have all the fancy features (there is no Wi-Fi app integration, for example), as it is the case at this price range.
Buying Guide: Choosing a Window AC for a Large Room
It is important to choose the proper window air conditioner that will be able to cool a large room and not to spend energy in vain. These are some of the major considerations and guidelines to take into consideration when purchasing a large-room window AC:
BTU Capacity and Room Size
Correspond the BTU rating to the square footage of your room. Generally speaking, you should have 20 BTUs of cooling capacity per square foot of room space (average ceiling height and insulation). As an example, a 500 sq. ft. room may require an approximate 10,000 BTU unit and a 700 sq. ft. room may require an approximate 14,000 BTUs.
It is safer to oversize a little on large rooms, and particularly when the room is high, or exposed to the sun, or is apt to be hot. The models discussed above all fall in the 12,000-18,000 BTU category, which is ideal to use in large spaces.
Do not under-size it (the AC will not be able to cool and will run all the time) and do not over-size it grossly. An oversized AC will short-cycle (turn on and off too often) and fail to dehumidify the air, resulting in a chilly, but sticky room.
Select a BTU that suits your particular room size and conditions. The manufacturers usually give an approximate coverage area, take that as a guide and consider the room details: is the room badly insulated or is it on the upper floor with heat rising, go a bit bigger.
115V vs. 230V Units
The two types of electrical BTU window ACs are standard 115V or 120V (the kind you plug into a regular household outlet) and 230V (the kind that needs a special outlet such as a dryer or range). In general, window ACs that are larger than ~15,000 BTUs are 230V.
As an example, our 18k BTU selections require 230V circuits, but the 12k-15k BTU units operate on 115V. Test the capacity of your home: unless you can easily add a 230V outlet to the room, you will have to settle with a 115V model.
Luckily, there are a lot of large-room ACs (up to ~14k-15k BTU) that come in 115V form that can be used on a dedicated 15 or 20 amp circuit. The circuit should always be capable of the amperage draw of the AC (large units may require 10-15 amps; a dedicated circuit is advisable to avoid tripping breakers).
Energy Efficiency (EER/CEER)
A unit that will most probably consume many hours in a large space is very important in terms of energy efficiency. Look at the EER (Energy Efficiency Ratio) or CEER (Combined Energy Efficiency Ratio) – the higher the number the more cooling you get per watt of electricity. A certified AC that is Energy Star is more than average in efficiency.
As an example, an inverter such as the LG or Friedrich has a CEER of 14-15 which is outstanding, whereas a typical large unit may be 10-11.8 CEER. A more efficient unit can save a lot on the electricity bills over a summer, particularly in a large room where the cooling cycles are longer.
Efficiency improving features: seek an “Eco” or Energy Saver mode (which switches the fan off when the compressor is off, rather than running the fan all the time). Additionally, you can also think of units that have programmable thermostat and timers to avoid wasting cooling when you do not need it.
Inverter ACs are more efficient by nature since they do not stop and start but instead vary the speed, they are worth the investment in large rooms you frequent even though they are more expensive to purchase.
Noise Level
In a big room AC, particularly when it is a living room or a bedroom, noise may be a determining factor. The traditional AC units are noisy with compressor and fan on high setting, with noise levels in the middle 50s and 60s dB range.
In case you intend to use the AC when you are sleeping or watching the television, a quieter one would be better. Here, inverter units (such as LG, Midea U, Friedrich Chill Premier) have a large advantage since they remove the abrupt compressor kick-on sound and tend to operate at lower speeds most of the time, which drastically reduces noise.
The Midea U, to give one example, is one of the quietest designs out there (about 42 dB on low) and the LG and Friedrich are also very quiet at low speeds.
When you choose a standard unit, do not forget to look at user reviews on noise feedback. Noise can also be reduced by proper installation of the unit (use the foam insulation strips to eliminate vibration in the window, make sure that it is sitting level). Keeping the sound down will be achieved by running the fan on a lower setting where possible.
Other ACs specify a dB level – in that case, what is the setting at which it is measured. Features such as quiet mode or Sleep mode can come in handy; these tend to slow down the fan or alternate cooling to ensure that the sound is more tolerable at night.
Smart Features and Controls
Most of the new window ACs in large rooms are smart: they have Wi-Fi and mobile apps, support voice assistants, etc. These can be very convenient. You can switch the unit on/off or alter the settings using your phone anywhere with a Wi-Fi enabled AC, or you can use Alexa/Google to control it with your voice.
This is useful in pre-cooling a room or controlling AC when you are not at home (e.g. switching it off when you forget, or switching it on when you are on your way home). A smart AC may cost a little extra, all other things being equal, but it may be worth it in terms of flexibility and possible energy savings (because you are less likely to run it all the time).
At least, make sure the unit has a full-function remote, even when you do not need Wi-Fi. Almost all do. Make sure that the remote can adjust all modes, temperature, fan speed and timer. There are also remotes with in-built temperature sensors (such as the Follow Me feature) which can cool to your location in the room more precisely.
It is better to have electronic controls that have a digital thermostat to enable you to set a particular temperature. Easier mechanical-dial large ACs are hard to find, but in case you come across one, be aware that you will not have as precise control.
Installation Considerations
Big window AC units are heavy and therefore, installation is very important in terms of safety. Read the instructions of the manufacturer carefully. The following are tips:
- Window type and size: Make sure that your window is big enough to fit the dimensions of the unit (width and height clearance). A majority of them need a double-hung window. Accordion panels were used to seal the gaps. You might have to use a smaller unit or a through-the-wall installation kit in case your window is too narrow.
- Support bracket: Units weighing more than ~100 lbs, it is strongly advised to use a steel AC support bracket which is mounted to the exterior wall or window frame. This supports the weight of the unit and avoids the possibility of the unit falling and breaking the window. Certain larger Friedrich/Frigidaire models have built-in slide-out chassis which are incorporated with certain brackets or wall sleeves.
- Two-person lift: Never try to put a large AC in the window by yourself. Get an assistant to hold the window sash or help in directing the unit. Put on gloves (the metal edges are sharp).
- Tilt angle: The majority of window units must be tilted outward to allow condensate to drain. This will be spelt out in the manual. Leakage of water is avoided by proper drainage.
- Sealing and insulation: Apply the foam strips and side panels that come with it to seal around the unit. This prevents hot air and bugs and makes it more efficient. In very large units, you should also ensure that there are no gaps in the window frame after installing it.
Maintenance and Usage Tips
After you have installed your AC, a little care will keep it going:
- Make sure to clean the filter. Big ACs circulate a lot of air and this implies that the filter will trap a lot of dust. A blocked filter slows down the airflow and performance. The majority of units feature a reusable filter that is easy to access and can be vacuumed or rinsed every few weeks (and most have a filter check reminder light).
- Inspect the condenser coils (the outdoor fins) once a season. Don not allow them to be dirty, filled with leaves or debris. Wash them (with power off) by gently brushing or hosing them off, when they get dirty, clean coils help the AC to dissipate heat.
- Check amperage: ACs that are large should preferably be on a dedicated circuit. Do not use extension cords or power strips, because the large current draw may cause a fire. In case of an absolute necessity of an extension it should be a heavy-duty one with a specific AC rating.
- Be smart with the thermostat: Put a sensible temperature (e.g. 75º F) instead of something very low such as 65º F. The unit will continue to run until it reaches the set point, setting it very low does not cool any faster, it just keeps it running.
- You can also use the timer or a smart schedule to switch the AC off when you are out and on just before you come back home to save energy.
- Off-season maintenance: During winter or off-season, the unit should be taken out of the window (most preferable to extend the life of the unit) or covered and sealed to avoid cold drafts. In cold climates, large window units are removed by many people every fall to preserve them against the elements and re-installed in spring.
To conclude, pay attention to the size of the unit that is right and efficient, and, in case noise or convenience is important to you, pay attention to the inverter and smart models. All of the above recommended ACs have their own advantages: the Midea U is as silent as a whisper, the Friedrich and Keystone are just plain brutes.
With an evaluation of what your room requires and the above guide, you will be well on the way to a comfortably cool (and not outrageously costly) large room. Stay cool!
