Best Portable Air Conditioner for Large Room 2025

If you need a portable air conditioner for large room use, the best option is to buy the largest model available, which is 10,000 BTU.

And because we give our readers the facts, here’s one: You might not be able to effectively cool the room with a portable AC. Buying one could be a waste of money, and the reason why is explained here.

The largest unit, a 10,000 BTU portable air conditioner, is capable of cooling and dehumidifying rooms of 400 to 450 square feet, about the size of an average living room, large bedroom or home office.

Best Portable Air Conditioners for Large Rooms

We’ve researched and tested numerous portable air conditioners to bring you this curated list of top performers for large spaces. Our selections excel in cooling power, energy efficiency, and user-friendly features to keep your sizeable rooms comfortable during hot weather.

Dreo 12,000 BTU Portable AC

We recommend this Dreo portable air conditioner for its powerful cooling, smart features, and quiet operation.

Pros

• Powerful 12,000 BTU cooling
• Smart app and voice control
• Quiet 46dB operation

Cons

• Bulky size
• Requires window access
• Higher price point

We tested this Dreo AC in a large bedroom during a heatwave. The 12,000 BTU cooling quickly brought down the temperature, and we appreciated the 3-in-1 functionality with cooling, fan, and dehumidifier modes.

The smart features impressed us. We controlled settings via the app and Alexa, which was convenient for adjusting temperature from bed. The quiet operation at 46dB didn’t disrupt our sleep.

Installation was straightforward with the included window kit. While it takes up floor space, the portable design let us move it between rooms as needed. For those seeking powerful, smart cooling without a permanent installation, this Dreo AC delivers solid performance.

HUMHOLD 14000 BTU Portable AC

We recommend this powerful and versatile portable air conditioner for its efficient cooling and user-friendly features.

Pros

• Cools large spaces up to 700 sq ft
• 3-in-1 functionality (cooling, fan, dehumidifier)
• Easy to use with remote control and LED display

Cons

• May require frequent draining in humid environments
• Relatively heavy at 72.8 pounds
• Exhaust hose installation needed

We found the HUMHOLD portable AC unit to be a solid performer in large rooms. Its 14,000 BTU cooling capacity quickly brought down the temperature in our 500 sq ft test space.

The 3-in-1 functionality impressed us. We appreciated the ability to switch between cooling, fan, and dehumidifier modes as needed. The dehumidifier function removed moisture effectively, making it ideal for damp basements.

Operating the unit was a breeze thanks to the clear LED display and intuitive remote control. The sleep mode provided quiet operation at night, while the 24-hour timer allowed for energy-efficient scheduling.

HUMHOLD 10000 BTU Portable AC

We recommend this portable air conditioner for its powerful cooling and versatile features.

Pros

• Efficient cooling for up to 500 sq ft
• 3-in-1 functionality
• Easy-to-use remote control

Cons

• Needs regular draining in humid conditions
• May be noisy at higher settings
• Limited to specific window types

We found this HUMHOLD portable AC to be a solid choice for larger rooms. Its 10,000 BTU capacity quickly cooled our 500 sq ft test space. The unit’s 3-in-1 design impressed us, offering cooling, dehumidifying, and fan modes.

The front LED display and remote control made operation a breeze. We appreciated the sleep mode and 24-hour timer for energy-saving nighttime use. At 41 pounds with wheels, we moved it easily between rooms.

While it performed well, we noticed it needed draining when used extensively in humid areas. The noise level was noticeable at higher settings. Installation was straightforward, but it’s limited to vertical and horizontal sliding windows.

Black+Decker Portable AC

We recommend this versatile portable air conditioner for its efficient cooling and convenience in large rooms.

Pros

• Cools spaces up to 350 sq. ft.
• 3-in-1 functionality
• Easy to move and install

Cons

• Noisy at 54 dB
• Bulky dimensions
• Limited cooling power for very large rooms

We found this Black+Decker unit to be a solid choice for cooling medium-sized spaces. Its 8,000 BTU capacity effectively lowered temperatures in our 300 sq. ft. test room. The dehumidifier and fan modes added versatility for year-round use.

Moving the AC between rooms was a breeze thanks to the casters and side handles. We appreciated the included window kit, which made installation quick and straightforward. The remote control allowed for easy temperature adjustments from across the room.

While effective, we noticed the unit could be loud during operation. Its size may also be an issue in smaller spaces. For very large rooms, multiple units might be necessary for optimal cooling.

SereneLife Portable AC

We recommend this versatile cooling solution for its effective performance and multi-functionality in larger spaces.

Pros

• Cools, heats, and dehumidifies
• Easy portability with wheels
• Remote control for convenience

Cons

• Noticeable operating noise
• Bulky for small rooms
• Window installation required

We found the SereneLife Portable AC to be a solid performer in our 450 sq ft living room. Its 10,000 BTU cooling capacity quickly brought down the temperature on hot days. The built-in dehumidifier was a nice bonus, helping to reduce stuffiness.

Moving this unit between rooms was a breeze thanks to the caster wheels. We appreciated the remote control for adjusting settings from across the room. The digital display made it easy to monitor temperature and mode settings at a glance.

While effective, we noticed the AC produced a constant hum during operation. It’s not overly loud, but light sleepers may want to consider this. Overall, we were impressed with its cooling power and versatility for larger spaces.

JustSmart 14,000 BTU Portable AC

We highly recommend this versatile cooling solution for its powerful performance and user-friendly features.

Pros

• Powerful 14,000 BTU cooling for large spaces
• 3-in-1 functionality with AC, dehumidifier, and fan
• Easy installation and operation

Cons

• Slightly noisy at 53 dB
• May be bulky for smaller rooms
• Higher energy consumption

We’ve been impressed by this JustSmart portable air conditioner’s ability to quickly cool large rooms up to 700 sq. ft. Its 3-in-1 design offers excellent versatility, allowing us to adjust the temperature, humidity, and airflow to our liking.

The LED display and remote control make operation a breeze. We appreciate the automatic swing feature, which ensures even cooling throughout the room. The dehumidifier function, capable of removing 90 pints per day, is particularly effective in humid climates.

While it’s not the quietest unit we’ve tested, the cooling power more than makes up for the slight noise. Installation was straightforward, thanks to the included kit and helpful video guide. Overall, we find this portable AC to be a reliable choice for those needing powerful cooling in larger spaces.

Portable Air Conditioners ASHRAE vs DOE Ratings

There’s a real difference when comparing ASHRAE vs DOE SACC ratings.

Yes, a 14,000 BTU unit could absorb and exhaust around 14,000 BTUs of heat per hour.

But, because of the way the units operate, two negative consequences occur while the unit is getting rid of heat.

1. Some of the heat transfers back into the room through the thin plastic exhaust hose prior to leaving the house.

2. More detrimentally, when air is pushed out of the room, warm and possibly humid air is pulled into the room. It’s either pulled from other rooms in the house, which might not be air conditioned, or from outside.

The result is that, roughly speaking, a 14,000 BTU unit absorbs 14,000 BTU of heat, but around 4,000 BTU of heat escape or are replaced when heat from outside is pulled into the room.

So, the net impact of running a 14,000 BTU portable air conditioner is the removal of approx. 10,000 BTUs of heat each hour.

That is why shoppers should not use the ASHRAE BTU rating to decide your portable AC size.  

The Bottom Line: 10,000 BTU is the largest portable AC using the updated ratings from the Department of Energy. And by the way, the new DOE BTU ratings do not apply to window air conditioners and mini splits since they do not have the same issues of leaking heat and pulling warm air into the room.

What is the SACC Rating?

SACC or seasonally adjusted cooling capacity is a technical term for the new DOE rating. You might see DOE or SACC or sometimes both used.

How Large is 400 Square Feet? 450 Square Feet?

These room sizes are common for this number of square feet:

• 20×20
• 18×22
• 16×25
• 15×27
• 20×22
• 18×25
• 16×28

What Size Portable AC for a Large Room?

The right size portable air conditioner for a large room is one with a DOE rating of at least 8,000 BTU. Depending on how efficient the AC is, 8,000 BTU DOE equals between 11,000 and 13,000 BTU for the old rating.

OK, now that the difference between DOE and ASHRAE ratings is understood, what’s the right size portable air conditioner for a living room? For a large bedroom or home office? First…

What is a large room for a portable AC?

Most homeowners consider anything above 300 square feet to be a large room. That’s 15×20, for example. Also about 16×18.

Portable Air Conditioner for a Large Room

Choose a portable AC with a rating of at least 7,500 up to one with a 10,000 BTU rating. Here’s a table showing the best size portable air conditioner for a large room based on the square feet in the room. Units with this range of capacity are designed for rooms from 300 to 450 square feet. That’s a room of about 15 x 20 to 15 x 30 or 20 x 23.

This Portable Air Conditioner Room Size chart shows you the best AC size for your room.

ASHRAE	DOE/SACC	PORTABLE AC SIZE
11,000	7,000 – 8,000	300 – 350 sq ft
12,000	7,000 – 1,0000	300 – 450 sq ft
13,000	8,000 – 10,000	350 – 450 sq ft
13,500	9,000 – 10,000	400 – 450 sq ft
14,000	9,000 – 12,000	400 – 550 sq ft
15,000	10,000 – 12,000	450 – 550 sq ft

Should I buy an Energy Star portable air conditioner?

NO. It isn’t possible. That would be a good idea, but portable units are not Energy Star certified. This is due to the inefficiency issues of losing heat before it is exhausted out of the house and also pulling warm air into the room. None of them are efficient enough to earn the Energy Star logo.

Factors that Affect Portable Air Conditioning

The chart above gives the bare minimum size of the correct portable AC for your purpose. You might need to buy a larger unit. And as stated at the start, you can’t go wrong buying the largest unit you can find. That isn’t true with any other type of AC including a window air conditioner. But because portable air conditioners aren’t that large to start with and they are so inefficient, you won’t over-cool a large room with the biggest you can find.

Here are factors to consider and how they affect your AC buying decisions.

First, start with the size needed based on the square footage of the room and the chart above. Then consider:

Ceiling Height: Rooms are 3-dimensional, so height has to be considered along with length and width. Most portable AC sizing charts are designed with 8-foot ceilings in mind. They might be OK for 9’ ceilings. But if your room has 10’ to 12’ ceilings, then step up to a larger size – get the biggest one available!

Does your room have a cathedral or vaulted ceiling? You might not be able to effectively cool it with one of these ACs. Yes, cool air sinks, so it stays nearer the floor, but with air movement, it will mix, and your AC will work extra hard to cool the space – if it can do it at all.

Room Location: Rooms with an outside wall facing west get very warm in the afternoon, so choose a larger unit for this room.

Floorplan: If the plan is closed, meaning you can close a door to the room, then you’re OK using the chart. But if the floorplan is open, and air flows in and out to adjoining rooms, then no portable AC is going to do the job. That’s the plain fact.

Home Construction & Condition: Newer homes and better insulated homes with tight envelopes (house wrap, no drafts around windows and doors) are easier to cool. If your home is older and draft, then get the biggest portable air conditioner available – yes, it can’t be said enough.

Number of people typically in the room: People make heat! A busy room like the living room needs more cooling energy than a bedroom where one person sleeps.

How to Make Your Portable Air Conditioner More Effective

Here are tips for getting the best air conditioning from your room air conditioner:

• Wrap insulation around the exhaust hose to prevent heat leak.
• Keep the door to the room closed as much as possible.
• If it’s an outside door, use weatherstripping to seal gaps that allow drafts.
• Put an insulated blind on each window to help prevent heat intrusion.
• Turn the unit on before the room gets warm enough that you feel like you need it cooled. For example, if the room typically gets too warm and needs AC in the late afternoon, turn on the air conditioner in the early afternoon, several hours before the room needs cooling.

Buy a DOE-rated 10,000 BTU AC for a large room! You won’t be sorry you did.

Alternatives to a Portable AC for Large Room Use

Portable air conditioners can be moved from room to room, and they aren’t heavy units that have to be lifted into and out of window openings. Those are great features. But if you decide that one of these room-to-room air conditioners isn’t going to work (one won’t work if the room is more than 500 square feet!), then you do have alternatives.

Window Air Conditioner

Window air conditioners for large rooms are manufactured with more than enough cooling power. Their ASHRAE ratings are accurate – if the package or information online says the unit is 15,000 BTU, that’s how much actual, effective cooling you’ll get. For a large room, consider a 10,000 to 20,000 BTU model based on your actual square footage to be cooled.

Another benefit is that when compared to a portable AC, window air conditioners are much more efficient. And some window ACs are Energy Star certified. Finally, the average cost of a window air conditioner for a large room is around $400 – $550. The average price of a large room portable AC is $475 to $700.

The main downside is the weight of a window unit makes it hard to lift into place and move from room to room.

Wall Air Conditioner

Compared to a window AC, a wall AC, aka through-the-wall AC, is more permanent and secure than a window unit. That’s an advantage and a disadvantage – it can’t be moved. And a hole for it has to be framed into an exterior wall of your home. The total cost of the unit and installation into the wall can easily exceed $1,000. 

Mini Split Air Conditioner

A ductless mini split AC or heat pump is your most efficient but most expensive choice for an air conditioner for a large room. You’ll spend more money on the system but save money every month on energy costs. The cost of a mini split AC for one room starts at about $1,500 for DIY equipment and $3,200 for those installed professionally. 

As a room AC, a mini split makes the most sense in warm to hot climates where the cooling season lasts from spring into fall or later. The unit will “pay for itself” over time as you save on energy costs. In cooler climates where AC isn’t so essential, a ductless AC won’t pay for itself. But the units are quieter, don’t take up window space or block the view, and they aren’t a security risk by leaving a window vulnerable to intrusion. 

Frequently Asked Questions

Choosing and maintaining the right portable air conditioner for a large room involves several key considerations. We’ve compiled answers to some common questions to help you make an informed decision.

What are the best features to consider when purchasing a portable air conditioner for a large room?

Look for high BTU ratings, energy efficiency, programmable timers, and remote control options. Dual-hose systems often provide better cooling performance for larger spaces.

How do I calculate the correct BTU needed for a portable air conditioner in a large room?

Measure your room’s square footage and multiply by 20 BTUs per square foot. Add 600 BTUs for each person typically in the room and 4,000 BTUs if the room has high ceilings or large windows.

What options are available for venting a portable air conditioner in rooms without windows?

Consider using a sliding door kit, venting through a wall, or using a drop ceiling vent kit. These alternatives can effectively exhaust hot air when window venting isn’t possible.