Why not get the biggest window air conditioner?
If you have to install just a window AC unit and are looking to get as much cooling effect as possible, you should buy the biggest window AC unit there is. Window air conditioners for large rooms can effectively cool down places with 1,500+ sq ft.
The size of any air conditioner is measured in BTU or tons (1 ton = 12,000 BTU). The size of window air conditioners ranges from 5,000 BTU to 24,000+ BTU.
Note: There is only 1 unit currently on the market that can generate a full 25,000 BTU cooling output with superb energy efficiency (EER rating above 10). This is the #1 FRIGIDAIRE FFRE253WAE (you can check it in the comparison table below) which is absolutely massive, and the largest window air conditioner currently on the market.

Any window AC unit with above 15,000 BTU is considered a large room unit. Up to 15,000 BTU, you still have 110V units; above that, you have to use 230V voltage. You can check out the largest AC units still powered by 110V here.
Figuring out which window air conditioner is the biggest is easy:
Just round up all the big 20,000+ window AC units on the market, and rank them by the cooling capacity (these are some big 100+ lbs units that generate a tremendous cooling output; 2-ton window AC units).
This is exactly what we did; you will find a list of the biggest large room window AC units below. If you’re in a hurry, you can jump to the complete comparison of these massive window AC units with reviews here:
Skip To Comparison Of 24,000+ BTU Window AC Units Here
First, however, it does make sense to familiarize ourselves a bit what to look for when buying a window air conditioner for a large room.
Before we check the comparison of the best units by Frigidaire, Koldfront, LG, and Amana, we will cover the basic specifications.
These include the BTU cooling output and coverage area, energy efficiency (cost-saving EER rating) based on rated big window AC electric input, and airflow levels these giant window AC units have to produce:
What Is The Largest Window Air Conditioner You Can Get? (BTUs And Sq Ft Coverage)
Unlike portable AC units, window AC units can generate a tremendous amount of power. We usually use BTUs (BTU/hr) as a unit for the unit’s cooling output.
With the biggest window air conditioners for large rooms, we can use tons. The biggest window AC units can produce 2 tons of cooling output. The largest one – the #1 FRIGIDAIRE FFRE253WAE in the comparison table below – can generate 25,000 BTU; this is equal to 2 1/12 tons.

The key part when buying large room window AC units is to adequately size these 2-ton window air conditioners to your area. All 2-ton units can cover up to 1,500 sq ft.
The biggest 25,000 BTU FRIGIDAIRE FFRE253WAE has the largest coverage area of any window AC unit: Up to 1,600 sq ft.
With such large window AC units, you have to be careful not to oversize your unit. If you’re looking to cool down an area of 800 sq ft or smaller, you don’t actually need the large room window AC units. 15,000 BTU units would serve better in those cases.
One of the most important specifications for these enormous window AC units is energy efficiency:
Energy Efficiency (EER Rating Of Large Room Window Air Conditioners)
The bigger the AC, the more power it will draw. That means that energy efficiency becomes exceedingly important when choosing a window air conditioner for larger rooms.
The largest window AC units draw anywhere from 2300W to 3000W to produce about 2-tons of cooling effect. The closer you get to the lower limit – 2300 watts – the less you will spend on electricity.
Energy efficiency itself is expressed as an EER rating. This is basically a ratio between electricity input (wattage) and cooling output (BTUs or tons).
The average EER rating of bigger window AC units is about 9. That means that such a unit would require about 2700W to produce 24,000 BTU of cooling power. You want to get a better energy efficiency than that.
That’s why we included only the above-average energy-efficiency units in the comparison below. If you look at the EER ratings of these large room air conditioners, you can notice that all of them – with the exception of #2 Koldfront WAC25001W – have an above 10 EER rating.

That alone can save an additional 10% on electricity (compared to #2 Koldfront WAC25001W) by choosing other 10+ EER units. 10% is about $26 savings per year. In 20 years, you can save more than $500 just by choosing a large window AC unit with superb 10+ EER rating energy efficiency.
Adequate Airflow For Avoiding Hot Pockets
With such large window air conditioners, you really need to be careful about airflow. A window unit serves as the single point from which 2-tons of cooling output originates.
For these units to homogeneously cool down spaces up to 1,600 sq ft, they need to have above 300 CFM airflow. The airflow pushes the cooled air throughout the space; this is essential to avoid the so-called ‘hot pockets’.
If a big window AC unit would have an airflow below 300 CFM, that really wouldn’t be a unit appropriate for cooling down large rooms or spaces. The cool air just wouldn’t be distributed evenly enough due to insufficient airflow.
In the comparison table of the biggest window air conditioners for larger spaces below, you can see that all of them do generate 300+ CFM airflow. The #3 LG LW2516ER 24,5000 BTU unit can even produce 500+ CFM of airflow, allowing for very fast and homogenous cooling.
With all this in mind, let’s have a look at what are the largest window air conditioners you can get:
Biggest Window Air Conditioners For Large Rooms (Comparison + Specs + Reviews Below)
Biggest Window ACs: | #1 FRIGIDAIRE FFRE253WAE | #2 Koldfront WAC25001W | #3 LG LW2516ER | #4 AMANA AMAP242BW |
---|---|---|---|---|
Photo: | ![]() |
![]() |
![]() |
![]() |
Cooling Capacity: | 25,000 BTU | 25,000 BTU | 24,500 BTU | 24,000 BTU |
Cooling Area: | Up to 1,600 sq ft | Up to 1,500 sq ft | Up to 1,560 sq ft | Up to 1,500 sq ft |
EER Rating: | 10.3 | 9.4 | 10.3 (CEER) | 10.4 |
Power Input: | 2430W (230V, 10.6A) | 2660W (230V, 11.3A) | 2370W (230V, 10.9A) | 2300W (230V, 10A) |
Airflow: | 388 / 424 / 460 CFM | N/A | 530 CFM | 447 CFM |
Price: | $$$$ | $$$$ | $$$$ | $$$$ |
Average Rating: | ![]() |
![]() |
![]() |
![]() |
Availability: | Check Price | Check Price | Check Price | Check Price |
1. Biggest Window Air Conditioner With 25,000 BTU: FRIGIDAIRE FFRE253WAE

Cooling Capacity: | 25,000 BTU |
Cooling Area: | Up to 1,600 sq ft |
EER Rating: | 10.3 |
Power Input: | 2430W (230V, 10.6A) |
Airflow: | 388/424/460 CFM |
Dimensions (HxWxD): | 26.5″ x 26.5″ x 18.6″ |
Weight: | 148 lbs |
Price: | $$$$ |
Rating: | ![]() |
FRIGIDAIRE FFRE253WAE is, by and large, the biggest and the best large room window air conditioner. It is the only stand-alone AC unit that can generate an enormous 25,000 BTU of cooling output at superb 10+ EER rating energy efficiency. This is the flagship FRIGIDAIRE’s unit that can, by itself, cool down spaces up to 1,600 sq ft.
As we have seen thus far, the biggest window AC units have a 24,000 BTU cooling capacity; these are 2-ton window AC units. FRIGIDAIRE FFRE253WAE adds another 1,000 BTU to that overall cooling effect. With a total of 25,000 BTU capacity, it can adequately cool down huge rooms with up to 1,600 sq ft combined area.
The important part is that it can do it very effectively. To produce 25,000 BTU or 2 1/12 tons, FRIGIDAIRE FFRE253WAE requires only 2430W of electricity. Because it draws only a little over 10 amps, it has a superb 10.3 EER rating. This alone can generate $500+ of electricity savings over its lifespan compared to standard big window AC units.
On top of that, FRIGIDAIRE FFRE253WAE generates ample airflow to distribute the generated cold air evenly across the 1,600 sq ft places. With its max. airflow of 460 CFM, it has far more than the required 300 CFM to avoid the creation of undesirable ‘hot pockets’.
FRIGIDAIRE FFRE253WAE is by far the best window air conditioner for large rooms. It’s the biggest, has ample airflow, has superb 10.3 EER rating energy-efficient, and made by FRIGIDAIRE (a reliable company in the HVAC world). On top of that it’s available at a very affordable cost for a 25,000 BTU unit:
2. Biggest Window Air Conditioner With Heater: Koldfront WAC25001W

Cooling Capacity: | 25,000 BTU |
Cooling Area: | Up to 1,500 sq ft |
EER Rating: | 9.4 |
Power Input: | 2660W (230V, 11.3A) |
Airflow: | N/A |
Dimensions (HxWxD): | 26.5″ x 26.5″ x 18.63″ |
Weight: | 136.5 lbs |
Price: | $$$$ |
Rating: | ![]() |
Koldfront WAC25001W is another 25,000 BTU window air conditioner; that’s the highest BTU any window AC unit currently on the market can generate. The difference between Frigidaire’s 25,000 BTU and Koldfront WAC25001W unit is that the latter requires higher energy input.
As such, Koldfront WAC25001W is the most powerful window AC unit if we look at the total wattage. To generate 25,000 BTU, Koldfront WAC25001W requires 2660W. That means that it is more powerful in terms of electricity input.
However, the higher electricity input for the same amount of cooling effect means that Koldfront WAC25001W is less energy efficient than the #1 Frigidaire unit. It has an EER rating of 9.4; below 10. That means that, yes, it will generate a tremendous amount of cooling output but at about 10% higher electricity cost.
The advantages of Koldfront WAC25001W are very useful, however. This is the largest window air conditioner with a heater. In the winter, the unit can generate 16,000 BTU of heating output.
On top of that, this is a window AC unit for large rooms with high moisture levels. It has a record-level dehumidification rate of 137 pints/day; that’s more than 2 dehumidifiers combined.
Koldfront WAC25001W rated coverage area is up to 1,500 sq ft.
All in all, Koldfront WAC25001W is the 2nd 25,000 BTU window air conditioner for very large rooms. However, it doesn’t have the excellent energy efficiency that the #1 Frigidaire unit has:
3. Biggest LG Window Air Conditioner For Large Rooms: LG LW2516ER

Cooling Capacity: | 24,500 BTU |
Cooling Area: | Up to 1,560 sq ft |
EER Rating: | 10.3 (CEER) |
Power Input: | 2370W (230V, 10.9A) |
Airflow: | 530 CFM |
Dimensions (HxWxD): | 26″ x 28.13″ x 17.7″ |
Weight: | 136 lbs |
Price: | $$$$ |
Rating: | ![]() |
LG is a very respectable HVAC company. Their air conditioners are both reliable and affordable. The biggest window air conditioner LG makes is the LG LW2516ER. It is capable of generating 24,500 BTU of cooling output and it is Energy Star certified.
Energy Star certification is awarded only to units with peak energy efficiency. To produce 24,500 BTU, LG LW2516ER requires 2370W of electrical input. That means that its combined EER rating is 10.3. In short, the largest LG’s window air conditioner is highly energy-efficient and lowers electricity bills.
With a 1,560 sq ft coverage area, you’ll need quite a bit of airflow for homogenous cooling. LG engineers have created LG LW2516ER as the a large window air conditioner with the highest airflow. The LG unit doesn’t generate only the required 300 CFM airflow. In fact, it can generate 530 CFM while operating at the highest fan speed setting. No other room air conditioner can manage to generate 500+ CFM airflow.
All in all, LG LW2516ER is a massive 2-ton+ Energy Star window AC unit with the highest airflow. It will adequately cool down rooms with a combined coverage area of 1,560 sq ft:
4. Top-Rated 24,000 BTU Window Air Conditioner For Big Rooms: AMANA AMAP242BW

Cooling Capacity: | 24,000 BTU |
Cooling Area: | Up to 1,500 sq ft |
EER Rating: | 10.4 |
Power Input: | 2300W (230V, 10A) |
Airflow: | 447 CFM |
Dimensions (HxWxD): | 26.42″ x 26.85″ x 18.74″ |
Weight: | 130 lbs |
Price: | $$$$ |
Rating: | ![]() |
AMANA AMAP242BW is the best 2-ton window air conditioner. It even has the highest energy efficiency than the #1 Frigidaire and the #3 LG unit, and can properly cover areas up to 1,500 sq ft.
To generate 24,000 BTU of cooling output, this big window AC unit requires only 2,300W of electrical input. If you calculate the EER rating, you can EER rating = 10.4. No other window air conditioner for large rooms has a higher EER rating. That means that AMANA AMAP242BW is the most energy-efficient window air conditioner for large rooms.
To distribute all that cooled air, the AMANA AMAP242BW generates 447 CFM of airflow. That’s more than enough to adequately and evenly distribute all the generated cool air into several rooms. With a 1,500 sq ft coverage area, you can use this one big window AC unit to cool down up to 6 rooms.
All in all, AMANA AMAP242BW is the most energy-efficient 2-ton window air conditioner. As such it’s one of the most popular big units you can install on your window sill:
This is how far HVAC engineering has gone. You can install an air conditioner with a 2+ ton cooling capacity right on your window sill. If you have any questions regarding these enormous window AC units, you can use the comments, and we’ll try to help you out.
which ones are the quietest?
Hello there, you can check which window AC units are the quietest here. To check out which is the quietest window AC for large rooms, you have to crack open the specs sheets. Frigidaire B09F6SVBNF has 58/59/62 dB noise levels, Koldfront WAC25001W doesn’t have specified noise levels, LG LW2516ER has 61/63/65 dB noise levels, AMANA AMAP242BW 58/60/62 dB noise levels. All these are indoor noise levels. So, given the available data, the #1 Frigidaire B09F6SVBN is the quietest window air conditioner for large rooms. Hope this helps.