Portable air conditioners account for almost 20 percent of the room air conditioner market, but our lab tests reveal that they deliver only mediocre performance. In fact, not a single model earns a recommendation in our ratings.
So our first and best advice is to buy a window unit, which can be both cheaper and more effective at cooling a room.
In this article
- Portable Air Conditioners: Small Large
- How CR Tests Portable Air Conditioners
More on Air Conditioning
We Tried It: The Chillwell 2.0 Portable Air Cooler
Best Portable ACs for a Home Office
How Effective Are Portable ACs?
Best Window Air Conditioners
But what if a portable AC is really your only choice? Do you live in a home that lacks central air conditioning and prohibits window AC? Do you have sliding windows? A window you don’t want to block off completely? (A U-shaped unit can help you address that problem, too.)
The upside of a portable AC—that it isn’t bolted to a window—is also its downside. Unlike a window AC, which uses outside air to cool the coils, a single-hose portable AC uses conditioned air from inside the room to cool the mechanicals. That creates negative pressure that causes warm, unconditioned air from nearby rooms to flow into the space you’re trying to cool. It becomes a struggle to maintain a comfortable temperature.
Below, we’ve highlighted eight of the top portable models from our lab tests. CR members can dive into our full portable air conditioner ratings for more options. You can also consult our air conditioner buying guide to learn more about portable ACs and window units.
Note that the Department of Energy recently changed its testing protocol, prompting manufacturers to change the BTU ratings for many models, listing both an older ASHRAE rating (which will likely be higher) and a DOE rating (likely to be lower). While the new rating system does a better job of mimicking real-world conditions, the DOE standard for portables is still not directly comparable with the benchmark for a regular window unit.
Best Small Portable Air Conditioners
Small portable ACs have a capacity of 5,000 to 8,500 BTUs per hour.
Best Large Portable Air Conditioners
Large portable ACs have a capacity of 9,000 to 15,500 BTUs per hour.
How CR Tests Portable Air Conditioners
In our portable air conditioner tests, we measure how long it takes a unit to lower the temperature of a test chamber from 90° F to 85° F. That takes an average of 20 minutes. By comparison, the best window air conditioners can cool the room by 10° F in about 15 minutes or less.
For brownout tests, we set the AC to its lowest temperature setting on cool mode with the fan speed on low. We then start the AC with the compressor on and lower the voltage to 100 volts. We test the unit in a room set to 90° F while the outdoor temperature is 120° F, letting the unit run for 40 minutes before cutting the power entirely. After 3 minutes, we restore power and let the unit run for an additional 20 minutes. These testing procedures help us determine whether the unit will turn off or fail to restart due to the reduced voltage (which results in increased heat buildup within the unit).
For noise tests, we position the AC near the test window and measure noise levels on both high and low fan speeds when set to cool mode.
In CR’s brand reliability survey, two brands—Frigidaire and Honeywell—earned a top rating for predicted reliability, and two other brands rate above par. Owner satisfaction, which is based on the proportion of our members who are extremely likely to recommend their AC, wasn’t quite as high, with most brands earning a midlevel rating.
We test portable ACs from over a dozen brands, such as Emerson, Friedrich, Frigidaire, Honeywell, LG, Midea, Whirlpool, and Whynter. If you’re looking for additional information on portable ACs, check out our air conditioner buying guide.
Allen St. John
Allen St. John has been a senior product editor at CR since 2016, focusing on digital privacy, audio devices, printers, and home products. He was a senior editor at Condé Nast and a contributing editor at publications including Road & Track and The Village Voice. A New York Times bestselling author, he's also written for The New York Times Magazine, The Wall Street Journal, and Rolling Stone. He lives in Montclair, N.J., with his wife, their two children, and their dog, Rugby.
