When you buy through our links, Business Insider may earn an affiliate commission. Learn moreI tested 14 portable ACs for cooling ability, energy efficiency, noise, and ease of use to find the best models you can buy.Whynter, LG, Midea; Business InsiderSummer is long gone, but severe wildfires are still sending temperatures soaring and air quality crashing across parts of the US. While they typically cost more than window AC units, the best portable air conditioners are a great solution in wildfire emergencies (especially in areas that don't regularly see sustained seasonal heat spikes, like much of the West Coast) since they can be moved from room to room, eliminating the need to buy a separate window unit for each space.
A note about using a portable AC during wildfires: Many portable air conditioners have some degree of filtration to combat poor air quality, though the EPA recommends opting for a dual-hose portable AC during smoky conditions. Four of the units in our guide — the Midea, Wynter, Friedrich, and EcoFlow models — have dual-hose designs. However, we recommend checking out our guide to the best air purifiers for the best air-filtering options.
To find the best portable air conditioner, I consulted with two experts and tested 14 units for cooling ability, energy efficiency, and ease of use. My top pick is the Midea Duo Smart Inverter Portable Air Conditioner; it does an outstanding job of cooling and was among the quietest models we tested. For a budget option, I recommend the LG Portable Air Conditioner. It'll save you about $350 and is more energy efficient, but you'll sacrifice some cooling power, and it's not WiFi-enabled.Among the best air conditioners, portable units come with slightly higher operational and upfront costs but boast several advantages compared to window ACs. They are often allowed in rentals where window units are not, are easier to store and install, and some roll effortlessly from one room to another. If you're unsure whether a portable AC is right for you, my comparison of portable air conditioners versus window air conditioners helps identify the differences.Learn more about how Business Insider Reviews tests and researches home products.The best portable air conditioners in 2024Best overall: Midea Duo Smart Inverter Portable Air Conditioner – See at AmazonBest budget: LG Portable Air Conditioner (LP0621WSR) – See at AmazonBest for large rooms: Whynter ARC-14S Dual Hose Portable Air Conditioner – See at AmazonQuietest: Friedrich Zoneaire Portable Air Conditioner (ZCP12DB) – See at AmazonBest with heat: Black+Decker Portable Air Conditioner (BPACT14HWT) – See at AmazonBest battery-powered: EcoFlow Wave 2 Portable Air Conditioner – See at REIBest overallIn my tests, the Midea Duo Smart Inverter Portable Air Conditioner (model MAP14S1TBL) was among the best at cooling and quiet operation. Its dual-hose design also meets the EPA's recommendation for use during smoky conditions.However, it used the most electricity. The Midea used about 0.2 kWh more than our budget pick, the most energy-efficient in our guide. Running your portable AC eight hours a day all summer would equate to an average extra energy cost of about $25 based on average electricity rates. The Midea Duo's unique hose-in-hose design replaces the hot air removed from your room with cool air for more efficient cooling. It's easy to install, though the hose doesn't stay clipped into the window slider. I had to use duct tape to keep it in place. While lots of portable air conditioners have smart phone connectivity, the Midea Duo Smart Inverter Portable Air Conditioner offers thoughtful features that others don't.James Brains/Business InsiderIt also has several smart functions not found in most other portable ACs. You can turn off the LED to avoid light pollution and set a "sleep curve" that adjusts the temperature throughout the night to balance comfort and power use. In the app, you can set the AC to turn on or off depending on whether you're home and control the airflow direction.The Midea Duo is also our best smart portable air conditioner because it works with the feature-packed SmartHome app (iOS and Android), pairing with Alexa or Google Assistant for voice control. I can turn the AC on/off and set a schedule from anywhere using my phone. I scheduled the Midea to turn off during surge electrical pricing and to come back on afterward to ensure the room is comfortable by bedtime. The Midea Duo is also available with a heating mode, though we haven't tested this model.Read our full Midea Duo Smart Inverter Portable Air Conditioner review.Best budgetConsidering its price and Btu rating, the LG LP0621WSR Portable Air Conditioner did a great job cooling. Our best budget portable air conditioner is designed for rooms up to 250 square feet but cooled the 550-square-foot testing room by more than 2 degrees in the two-hour testing period. That's pretty good.This performance was particularly impressive, considering it used the least power of any model in our guide.The LG LP0621WSR was easy to set up and install. Within 10 minutes of opening the box, I had it cooling the room. You'll need a Phillips-head screwdriver to secure the window panels. The panels fit a wide range of window sizes, a nice feature since I have extra-wide windows.The air conditioner is relatively light at 60 pounds and has handles, helpful for moving it from floor to floor. However, I ran into issues moving it from one room to another on the same level. The unit is low to the ground and top-heavy. It fell over as I rushed to roll it to the next room. Whether on low (55 decibels) or high speed (57 decibels), the LG LP0621WSR's noise output was average, about as loud as a quiet office or a normal conversation.LG has a newer, 7,000-Btu version, model LP0721WSR, if you need more cooling power. We haven't tested it yet, but it may be worth the $70 extra it costs to keep a midsize room cool.Best for large roomsThe first word that comes to mind when looking at the Whynter ARC-14S Dual Hose Portable Air Conditioner is "monolithic." With its large, imposing, flat front, our best portable air conditioner for large rooms looks like something from 2001: A Space Odyssey.Besides its appearance, the Whynter ARC-14S's most notable feature is its cooling abilities due to its dual-hose construction. With single-hose portable ACs, hot air is removed through the hose. This lowers the pressure in the room, causing hot air from outside the room to rush in to equalize the pressure. With two hoses, the Whynter replaces the removed air with cool air for more efficient cooling.The Whynter ARC-14S was the most effective portable AC we tested, but also the loudest.James Brains/Business InsiderIt was among the best in my cooling test, decreasing the room temperature by 3.6 degrees over two hours. However, it was also one of the loudest models, at 58 decibels. Weighing 86 pounds, the unit is heavy and lacks handles, making moving from room to room hard. The initial installation took me half an hour, which is longer than most models. It was slower because the fixtures needed to be screwed into the window slider by hand. The slider wasn't long enough for my 47-inch window opening, so I used Styrofoam packaging to fill the gap. Additionally, it doesn't come with foam seals, which are helpful for efficient cooling.Additionally, Whynter offers a version with heating capabilities, the ARC-14SH, which we also recommend.QuietestWhile our guide features several quiet portable air conditioners, the Friedrich Zoneaire Portable Air Conditioner (ZCP12DB) is the quietest, making it ideal for use in a bedroom. It's 54 decibels on high, less noisy than a normal conversation. It's 48 decibels on low, quieter than moderate rainfall. I slept undisturbed when I used it in my bedroom, as it didn't make any jarring sounds as the compressor turned on. The Friedrich is a dual-hose portable air conditioner. These tend to keep larger rooms cooler than single-hose units because they have a hose dedicated to air intake, which keeps hot air from leaking into the room. The Friedrich Zoneaire Portable Air Conditioner fully displayed the dual-hose cooling capabilities, decreasing the testing room's temperature by four degrees in two hours, the best in my tests. It did this using less power than most units.The quiet operation of the Friedrich Zoneaire Portable Air Conditioner makes it an excellent choice for bedrooms.James Brains/Business InsiderSetting up the Friedrich portable air conditioner was a breeze. It took 15 minutes, including connecting to the FriedrichGo app (iOS and Android). The only annoying part was hunting down a Philips screwdriver to install the batteries in the remote control. Reinstalling the AC in another room was hampered by the two hoses making it harder to just rest the slider on the unit. It wanted to flop around. It also didn't help that the unit arrived with a wheel busted off.If the Friedrich cools so well, why isn't it the top pick? The main reason is the price. It's $150 more than our top pick. Also, the app isn't as user-friendly. Still, if cooling power is your top consideration, the Friedrich Zoneaire Portable Air Conditioner is your best choice.Read our full Friedrich Zoneaire Portable Air Conditioner review.Best with heatIn addition to being one of the top performers in our cooling tests, the Black+Decker BPACT14HWT Portable Air Conditioner is the best portable air conditioner with heat, which makes it great for year-round use. I purchased it three years ago, and it's still going strong. I particularly like that I don't have to store it during the winter. Instead, I use it to heat the living room, which tends to run colder than the rest of the house. It's also available without heat.Installation took about five minutes, and I didn't need any special tools. I like that the window slider extends to 60 inches, which is more than enough for my needs. However, I wish it came with window security brackets to make it harder for someone to push the window open and gain access to my house. Fortunately, this hasn't been an issue.If you want to stretch your dollar by getting a unit that can make your space comfortable in both the winter and summer, the Black+Decker BPACT14HWT is your best bet.James Brains/Business InsiderIt's one of the louder units we tested, and when I neglected to clean the filter regularly, the Black+Decker produced jarring sounds as it changed fan speeds. In our tests, it was in the middle of the pack in electricity use. Over two hours, it consumed 1.83 kWh. We should also note that our air quality monitor registered a 50% increase in VOCs during testing. However, the levels weren't high enough to cause concern.Best battery-poweredThe EcoFlow Wave 2 is unlike any portable air conditioner I've tested. For one, it can be used without an electrical outlet, making it a smart option for summer power outages, camping, and other off-the-grid excursions. At 32 pounds, it's the lightest unit I've tested. Plus, it can heat your room.Setting up the Wave 2 took longer than most. Unlike most portable ACs, it doesn't come with a window slider. Instead, it has a 15-inch-by-9-inch foam block with cutouts for the two hoses. If your window opening isn't precisely this size, you're left to figure out how to fill the gap. I used another portable AC's window slider and plenty of duct tape. While you don't need a window to use the Wave 2, you do need an opening to the outside for the exhaust and air intake hoses. You operate the Wave 2 using the on-unit controls or the EcoFlow app (iOS and Android). Connecting to the app was seamless. The battery-powered EcoFlow Wave 2 Portable Air Conditioner keeps small spaces cool, even when there isn't an electrical outlet.James Brains/Business InsiderInitially, I tested the EcoFlow Wave 2 in my normal testing room while it was connected to a wall outlet. However, it struggled. It's only rated for spaces up to 108 square feet, about 20% of the testing area's size. While it ran quietly, it barely decreased the room's temperature. Since it is designed for on-the-go cooling in small spaces, I retested it using battery power in a 200-square-foot area. It did much better, lowering the temperature by two degrees. The Wave 2's battery lasts about three hours when running on max power. It can last up to eight hours on lower settings and takes about two hours to recharge. The battery conveniently attaches to the Wave 2 but adds 21 pounds to the unit's weight. You can also power the Wave 2 with solar, your car, or other batteries.As the best battery-powered portable air conditioner, the Wave 2 is expensive, costing $1,099 with the battery add-on. Still, I think the cost is worth it for such a versatile heating and cooling option. If you already have a portable power source, consider purchasing the Wave 2 without the battery. What to look for in a portable air conditionerWe use a decibel meter to measure sound output from each of the air conditioners.James Brains/Business InsiderBtu and room size: One British thermal unit (Btu) equals the heat needed to raise one pound of water by one degree Fahrenheit. In cooling, Btu measures how much heat is removed from a room. The more Btu per hour an air conditioner is rated for, the better job it does cooling.That said, you shouldn't just choose an AC based on Btu. You'll also want to consider room size. Higher Btu units are better at cooling larger spaces, but they're louder and will be too overpowering in smaller rooms (meaning unnecessarily high cooling costs). Use the table below (from the Energy Star website) to determine what Btu your room requires:Recommended Btu by room sizeRoom sizeCooling power needed100 to 150 square feet5,000 Btu150 to 250 sq. ft.6,000 Btu250 to 300 sq. ft.7,000 Btu300 to 350 sq. ft.8,000 Btu350 to 400 sq. ft.9.000 Btu400 to 450 sq. ft.10,000 Btu450 to 550 sq. ft.12,000 Btu550 to 700 sq. ft.14,000 Btu700 to 1,000 sq. ft.18,000 Btu1,000 to 1,200 sq. ft.21,000 Btu1,200 to 1,400 sq. ft.23,000 Btu1,400 to 1,500 sq. ft.24,000 Btu1,500 to 2,000 sq. ft.30,000 Btu2,000 to 2,500 sq. ft.34,000 BtuYour Btu needs will be greater if the room has a ceiling over 8 feet high, is very sunny, is regularly occupied by more than two people, or is a kitchen.Energy efficiency: Even the best portable air conditioners are not energy-efficient, and none are Energy Star certified. Still, if you're hoping to save some money on cooling costs or limit your carbon footprint, you'll want to consider energy efficiency. There are two factors to look at here: the compressor and kWh usage.A portable air conditioner's compressor pushes hot air outside so cold air can circulate in your room. Dual-inverter compressors, like the one in my top pick, are the most energy-efficient. These compressors have variable-speed motors that use much less energy than traditional compressors.To get an overall feel for your AC's energy usage, you'll want to look at kWh usage, short for kilowatt-hour. Most electricity utilities use kWh to measure your power use, and I use it to measure the energy consumption of the air conditioners I test. The lower the kWh usage, the better.Window size: Portable ACs usually come with a window slider, a long, adjustable piece of plastic that goes in your window's opening. The hose from your portable AC connects to the slider to send the hot air emitted from the unit outside. You'll want to measure your window before purchasing your AC to ensure the slider will fit.Noise: No one expects an air conditioner to be silent, but you'll want a unit with minimal noise output, especially if you use it while sleeping. We measure noise output with a decibel meter, but generally, you can expect units with more Btu to be louder. WiFi-enabled: Depending on your needs, you may consider a WiFi-enabled unit, which allows you to control the air conditioner from your phone. This makes setting a schedule or adjusting the settings easy without getting out of bed. Expect to pay a bit more for the convenience of app connectivity. How we test portable air conditionersI tested 14 portable ACs for overall portability, cooling abilities, energy efficiency, noisiness and more.James Brains/Business InsiderI have tested and reviewed air quality, cooling, and heating devices for six years, including 14 portable air conditioners. I also consulted with Enesta Jones, a US Environmental Protection Agency (EPA) spokesperson, and Joanna Mauer, the technical advocacy manager for the Appliance Standards Awareness Project.Based on my research and interviews, the main features to look for when shopping for portable air conditioners are how well they fit your window, energy consumption, and cooling abilities. Our testing methodology encompasses the following evaluation criteria.Setup: I timed how long it took to remove the packaging and install each unit, noting if tools were needed. Cooling: I set my home's heating system to 75 degrees. Once at the set point, I cranked the portable air conditioner to its highest fan speed and lowest temperature. Using a digital thermometer placed on the other side of the 550-square-foot testing room, I compared the before temp to the temperature two hours later to see how well the unit cooled.Noise: A loud air conditioner can make watching TV, working, or sleeping difficult. I measured each unit's noise output by holding a sound meter 6 feet from the AC as it ran on its highest setting. It lost points if the compressor made jarring sounds as it turned on and off.Power use: I measured how much energy each unit used while running on high for two hours using a smart plug. The least energy-efficient window air conditioner I tested still uses less power than the most efficient portable unit.Air quality: Before and after running the air conditioner for two hours, I compared particulate matter and VOC measurements using an air-quality monitor. I didn't weigh this category heavily, but I noted when there were significant changes in the air quality.Portability: I timed how long it took to uninstall the AC, move it to the next room, and reinstall it. Between the rooms, there is a 3/4-inch threshold, making handles advantageous. I also considered the air conditioner's weight.Extras: All units in this guide have at least a one-year warranty and a fan. ACs needed to have more than this to get extra points. For instance, a heating mode, remote control, dehumidifying, WiFi connectivity, foam seals for efficient cooling, and a longer warranty contribute to a more favorable assessment of a portable air conditioner.Portable air conditioner FAQsBelow we answer the most commonly asked questions about installing and using a portable air conditioner.James Brains/Business InsiderCan portable ACs help with wildfire smoke and air filtration?To some degree, yes. Most portable air conditioners have some degree of air filtration, and running your AC during smoke emergencies can help keep smoke out. However, the EPA recommends against using single-hose portable ACs during smoky conditions. Instead, opt for a dual-hose unit and ensure that the seal between the hose casing and the window is as tight as possible. Why do portable ACs have two Btu numbers?According to Mauer, the DOE Btu rating is more accurate than ASHRAE because it considers hot air infiltration and heat losses through the ducts.Mauer said ASHRAE, the manufacturer's Btu, doesn't account for the significant heat released back into the room by the exhaust hose. There is also no consistent testing standard.The DOE established standardized testing to account for the heat that ends up back in the room. My guide references the DOE ratings.What can you do if your AC doesn't have enough Btu to cool a room adequately?Mauer recommended keeping the filter clean. She also suggested closing the curtains and blinds during the day to reduce the room's heat gain and running a fan to circulate the cool air.Is a portable air conditioner or window air conditioner better?As outlined in my portable air conditioners vs window air conditioners article, window ACs are the better option for most people. In my tests, the most efficient portable AC still used 60% more power than my top window pick. The window unit also cost less and did much better cooling.I strongly recommend buying a window AC if you have a window that supports it. Portable units are only preferable when you don't have a single- or double-hung window.Can I use a portable air conditioner in a room without windows?Yes, but the hot air needs a way to leave the space. Otherwise, the unit won't provide any cooling benefits. Your portable AC just needs an opening big enough for the ventilating hose to send the exhaust outdoors.How do I clean and maintain my portable air conditioner?To keep your portable air conditioner working optimally, you need to clean the filter at least once a month, more if you use it frequently. Below are other cleaning tips to ensure you get the most out of your unit.Weekly:Remove condensation: Regularly remove the condensation that builds up from the cooling process. Many portable units make this easy with a built-in dehumidifier or drain hose. When you put the AC away for the season, remove condensation to avoid mold buildup.Keep the hose short: You can improve your portable air conditioner's efficiency and reduce dust and moisture buildup by keeping the hose as short and straight as possible.Wipe the exterior down: Run a damp cloth along the exterior of your unit to remove dust.Monthly:Clean the filter: A filter helps reduce allergens in your air and allows for optimal airflow. Follow the manufacturer's recommendations for how often to clean the filter. The best vacuums outfitted with a crevice tool attachment should get the job done. You can wash the filter with water, but ensure it dries completely before reinstalling it.Check the insulation: To keep your air conditioner running efficiently, check to make sure the insulation remains in place and seals any cracks. If your unit doesn't have foam seals, consider buying affordable adhesive strips. Apply insulation every time you move the AC.Twice per season:Vacuum the condenser coils: Grab a screwdriver and remove the back panel to access the condenser coils on the back of your unit. To keep your AC running efficiently, use a vacuum with the crevice attachment and run it lightly over the coils. Do not press hard; you don't want to dent the coils.Best overall: LG LP1419IVSM Smart Wi-Fi Portable Air ConditionerThe LG LP1419IVSM can be controlled by your phone, which is especially nice if you want to program your AC to run on a schedule.James Brains/Business InsiderDepartment of Energy (DOE) Btu rating: 10,000Recommended room size: 500 square feetWindow opening requirements: 6.5 inches by 23 to 60 inchesWarranty: 1 yearWeight: 71 poundsApp connectivity: Yes, iOS and AndroidExtras: Dehumidify, fan, remote control and mount, cord storage, window slider storage, foam seals, window security brackets, voice controlPros: Fits a broad range of window sizes, easy to move, can be scheduled and controlled with your phone, lowest energy use in our tests, performed well in cooling tests, Google Home and Alexa-enabledCons: Minimal warranty, longer setup than othersThe dual-inverter compressor of the LG Smart Wi-Fi Portable Air Conditioner (LP1419IVSM) sets it apart from other portable ACs. An AC with an inverter compressor is more energy-efficient thanks to a variable-speed motor. Other ACs simply turn on and off to regulate a room's temperature.Like all portable ACs, it isn't Energy Star-certified and still isn't as efficient as a window unit. In our energy use tests, it used 13% less power than the next most energy-efficient portable air conditioner we recommend: our budget pick, the LG LP0621WSR.You can use your phone as a remote and set a schedule using the LG ThinQ app (iOS and Android.) My kid has used the LG LP1419IVSM in their bedroom for three years and likes that they can use their phone to turn it on close to bedtime, so the room is cool when they get there. The LG portable AC was among the best portable air conditioners at cooling, only outperformed by the Whynter ARC-14S (our best portable air conditioner for large rooms). It does an outstanding job of keeping the room cool. Though it's not one of the quietest models (56 decibels, about as loud as a refrigerator), my kid likes that the white noise drowns out the city sounds.I like that this LG unit can fit windows up to 60 inches wide. However, installation took longer than other ACs I've tested. It's easy to maneuver from room to room thanks to a window-slider storage slot, smooth casters, and handles, though switching between floors can be a hassle with its 71-pound weight.Read our full LG portable air conditioner review.Best budget: LG LP0621WSR Portable Air ConditionerAt $318, the LG LP0621WSR was among the cheaper portable ACs we tested, but still a significant investment over a window unit.LGDOE Btu rating: 6,000Recommended room size: 250 square feetWindow opening requirements: 5.5 inches by 18 to 50 inchesWarranty: 1 yearWeight: 60 poundsApp connectivity: NoExtras: Dehumidify, fan, remote control, foam seals, window security bracketsPros: Good for cooling smaller rooms, low energy consumption (for a portable AC), easy to set up and install, fits a broad range of window sizes, relatively lightCons: Ran into trouble moving it from room to room, minimal warrantyAt its price and Btu rating, the LG LP0621WSR Portable Air Conditioner did a great job of cooling in our tests. It's designed to cool rooms of about 250 square feet, but it cooled our 550-square-foot testing room by more than 2 degrees in the two-hour testing period. That's pretty good.This performance was particularly impressive considering how much power it used. Only our top pick used less power. The LG LP0621WSR was easy to set up and install. Within 10 minutes of opening the box, I had it cooling the room. You'll need a Phillips-head screwdriver to secure the window panels. The panels fit a wide range of window sizes, a nice feature since I have extra-wide windows.The air conditioner is relatively light at 60 pounds and has handles, helpful for moving it from floor to floor. However, I ran into issues moving it from one room to another on the same level. The unit is low to the ground and top-heavy. It fell over as I rushed to roll it to the next room. Whether on low (55 decibels) or high speed (57 decibels), the noise output of the LG LP0621WSR was average, between a quiet office and a normal conversation.Best with heat: Black+Decker BPACT14HWT Portable Air ConditionerIf you want to stretch your dollar by getting a unit that can make your space comfortable in both the winter and summer, the Black+Decker BPACT14HWT is your best bet.James Brains/Business InsiderDOE Btu rating: 7,500Recommended room size: 350 square feetWindow opening requirements: 6 inches by 20.5 to 60 inchesWarranty: 1 year plus 5 years for compressorWeight: 68.3App connectivity: NoExtras: Heating, dehumidifying, fan, remote control, foam sealsPros: Excellent cooling, fast setup, five-year compressor warranty, heating modeCons: Loud operation, doesn't come with window security bracketsFor its price, the Black+Decker BPACT14HWT Portable Air Conditioner does a lot. In addition to being one of the top performers in our cooling tests, this workhorse also has heating capabilities for the colder months. I purchased this three years ago, and it's still going strong. I like that I don't have to put it in storage during the winter. Instead, I use it to heat the living room, which tends to run colder than the rest of the house.Installation was a breeze, taking about five minutes. I didn't need any special tools to get the job done. I like that the window slider extends to 60 inches, which is more than enough for my needs. However, I wish it came with window security brackets to make it harder for someone to push the window open and gain access to my house. Fortunately, this hasn't been an issue.It's one of the louder units we tested and when I neglect to regularly clean the filter, the Black+Decker produces jarring sounds as it changes fan speeds. In our tests, it was in the middle of the pack in electricity use. Over the course of two hours, it consumed 1.83 kWh. We should also note that our air quality monitor registered a 50% increase in VOCs during the testing period. However, the levels weren't high enough to cause concern.Best for large rooms: Whynter ARC-14S Dual Hose Portable Air ConditionerThe Whynter ARC-14S was the most effective portable AC we tested, but also the loudest.James Brains/Business InsiderDOE Btu rating: 9,500Recommended room size: 500 square feetWindow opening requirements: 6 inches by 20 to 46 inchesWarranty: 1 year + 3 years for the compressorWeight: 86 poundsApp connectivity: NoExtras: Dehumidifying, fan, remote control, hose covers, carbon filter, storage coverPros: Top performer in our cooling tests, comes with a storage cover, three-year warranty on compressorCons: Cumbersome to move, longer setup, one of the loudest units we tested, window slider only fits windows up to 46 inches long, doesn't come with foam sealsEditor's note: We link to and recommend the Whynter ARC-14S Dual Hose Portable Air Conditioner in our guide, but we actually tested model ARC-14SH. The only difference between the model we tested and what we recommend is that the ARC-14SH has heating capabilities but is perpetually out of stock. If you happen to find it in stock, we still recommend the ARC-14SH.The first word that comes to mind when looking at the Whynter ARC-14S Dual Hose Portable Air Conditioner is "monolithic." It looks like something out of "2001: A Space Odyssey" with its large, imposing flat front.Other than its appearance, the most notable feature of the Whynter ARC-14S is its cooling abilities. This is helped by its dual-hose construction. With single-hose portable ACs, the hot air is removed through the hose. This lowers the pressure in the room, causing hot air from outside the room to rush in to equalize the pressure. With two hoses, the Whynter replaces the air that's removed with cool air for more efficient cooling.It performed the best in our cooling tests, decreasing the temperature in the room by 3.6 degrees over two hours. However, it was also one of the loudest models at 58 decibels. Weighing 86 pounds, the unit is heavy and lacks handles, making it hard to move from room to room. The initial installation took me half an hour, which is longer than most models. It was slower because the fixtures needed to be screwed by hand into the window slider. The slider was just short of being long enough for my 47-inch window opening so I used some of the Styrofoam packaging to fill the gap. Additionally, it doesn't come with foam seals, which are helpful for efficient cooling.Best smart: Midea Duo Smart Inverter Portable Air ConditionerWhile lots of portable air conditioners have smart phone connectivity, the Midea Duo Smart Inverter Portable Air Conditioner offers thoughtful features that others don't.James Brains/Business InsiderDepartment of Energy (DOE) Btu rating: 12,000Recommended room size: 550 square feetWindow opening requirements: 10 inches by 19.05 to 63.86 inchesWarranty: 1 yearWeight: 75 poundsApp connectivity: Yes, iOS and AndroidExtras: Dehumidify, fan, remote control, foam seals, window security brackets, voice control, slider insulationPros: Outstanding cooling abilities, quiet operation, an app with several customization options, works with Alexa and Google Assistant, easy installation Cons: Uses a lot of power, oddly shaped hose, hose doesn't connect securely to window sliderWe had difficulty choosing between the Midea Duo Smart Inverter Portable Air Conditioner (model MAP14HS1TBL) and the LG LP1419IVSM Smart Wi-Fi Portable Air Conditioner as our guide's best portable air conditioner.The Midea unit did a slightly better job of cooling than the LG and ran quieter in our tests. The main reason the LG earned the top spot is it was much more energy-efficient. The Midea used an additional 0.4 kWh to produce similar cooling results. If you run your portable AC all summer, that would equate to an additional energy cost of about $90 on average. The drastic difference in energy efficiency outweighs the slight differences in cooling and noise performance, so the LG is in our top spot.The unique hose-in-hose design of the Midea Duo replaces the hot air removed from your room with cool air for more efficient cooling. It's easy to install, though the hose doesn't stay clipped into the window slider. I had to use duct tape to keep it in place. It also has several smart functions you don't see in most other portable ACs. You can turn off the LED to avoid light pollution and set a "sleep curve" that adjusts the temperature throughout the night to balance comfort and power use. In the app, you can set the AC to turn on or off depending on whether you're home or not and control the airflow direction.The feature-packed app (available for iOS and Android) pairs with Alexa or Google Assistant for voice control. I can turn the AC on/off and set a schedule from anywhere using my phone. I scheduled the Midea to turn off during surge electrical pricing and to come back on afterward to ensure the room is comfortable by bedtime. Read our full Midea Duo Smart Inverter Portable Air Conditioner review.What to look for in a portable air conditionerWe use a decibel meter to measure sound output from each of the air conditioners.James Brains/Business InsiderBtu and room size: This is short for British thermal units. One Btu equals the amount of heat needed to raise one pound of water by one degree Fahrenheit. In cooling, Btu is used to measure how much heat is removed from a room. The more Btu per hour an air conditioner is rated for, the better job it does cooling.That said, you shouldn't just choose an AC based on Btu. You'll also want to consider room size. Higher Btu units are better at cooling larger spaces, but they're louder and will be too overpowering in smaller rooms (meaning unnecessarily high cooling costs). Use the table below (from the Energy Star website) to determine what Btu your room requires:Btu needed by room sizeRoom sizeCooling power needed100 to 150 square feet5,000 Btu150 to 250 sq. ft.6,000 Btu250 to 300 sq. ft.7,000 Btu300 to 350 sq. ft.8,000 Btu350 to 400 sq. ft.9.000 Btu400 to 450 sq. ft.10,000 Btu450 to 550 sq. ft.12,000 Btu550 to 700 sq. ft.14,000 Btu700 to 1,000 sq. ft.18,000 Btu1,000 to 1,200 sq. ft.21,000 Btu1,200 to 1,400 sq. ft.23,000 Btu1,400 to 1,500 sq. ft.24,000 Btu1,500 to 2,000 sq. ft.30,000 Btu2,000 to 2,500 sq. ft.34,000 BtuYour Btu needs will be greater if the room has a ceiling over 8 feet high, is very sunny, is regularly occupied by more than two people, or is a kitchen.Energy efficiency: Even the best portable air conditioners are not energy-efficient, and most are not Energy Star certified. Still, if you're hoping to save some money on cooling costs or limit your carbon footprint, you'll want to consider energy efficiency. There are two factors to look at here: the compressor and kWh usage.A portable air conditioner's compressor works to push the hot air outside so cold air can circulate in your room. Dual-inverter compressors like the one found in our top pick are the most energy-efficient. These compressors have variable-speed motors that use much less energy than traditional compressors.To get an overall feel for the energy usage of your AC, you'll want to look at kWh usage, short for kilowatt-hour. It's a unit of energy that most electricity utilities use to measure your power use, and it's what we use to measure the energy consumption of the air conditioners we test. The lower the kWh usage, the better.Window size: Every portable AC comes with a window slider: a long, adjustable piece of plastic that goes in your window's opening. The hose from your portable AC connects to the slider to send the hot air emitted from the unit outside. You'll want to measure your window before purchasing your AC to ensure the window slider will fit your window.Noise: No one expects an air conditioner to be silent, but you'll want a unit with minimal noise output, especially if you use it while sleeping. We measure noise output with a decibel meter, but generally, you can expect units with more Btu to be louder. App connectivity: Depending on your needs, you may consider a unit with app connectivity, which allows you to control the air conditioner from your phone. This makes it easy to set a schedule or adjust the settings without getting out of bed. Expect to pay a bit more for the convenience of app connectivity. How we test portable air conditionersI have tested and reviewed air quality, cooling, and heating devices for the past five years and tested 12 portable air conditioners for this guide. I also consulted with Enesta Jones, a US Environmental Protection Agency (EPA) spokesperson, and Joanna Mauer, the technical advocacy manager for the Appliance Standards Awareness Project.Based on my research and interviews, the main features to look for when shopping for portable air conditioners are how well they will fit your window, energy consumption, and cooling abilities. Our testing methodology encompasses the following evaluation criteria.Setup: I timed how long it takes to remove the packaging and install each unit, noting if tools are needed to do the job. Cooling: I set my home's heating system to 75 degrees. Once at the set point, I cranked the portable air conditioner to its highest fan speed and lowest temperature. Using a digital thermometer placed on the other side of the 550-square-foot testing room, I compared the before temp to the temperature 2 hours later to see how well the unit cooled.Noise: A loud air conditioner can make it hard to watch TV, work, or sleep. I measured each unit's noise output by holding a sound meter 6 feet away from the AC as it ran on its highest setting. It lost points if the compressor made jarring sounds as it turned on and off.Power use: Using a smart plug, I measured how much energy each unit used while running on high for 2 hours. The least energy-efficient window air conditioner I tested still uses less power than the most efficient portable unit.Air quality: Before and after running the air conditioner for 2 hours, I compared particulate matter and VOC measurements using an air-quality monitor. I didn't weigh this category heavily, but I noted when there were significant changes in the air quality.Portability: I timed how long it took me to uninstall the AC, move it to the next room, and reinstall it. Between the rooms, there is a 3/4-inch threshold, making handles advantageous. I also considered the air conditioner's weight.Extras: All units in this guide have at least a one-year warranty, fan, and dehumidifying modes and remote controls. ACs needed to have more than this to get extra points. For instance, a heating mode, WiFi connectivity, foam seals for efficient cooling, and a longer warranty contribute to a more favorable assessment of a portable air conditioner.Portable air conditioner FAQsBelow we answer the most commonly asked questions about installing and using a portable air conditioner.James Brains/Business InsiderWhy do portable ACs have two Btu numbers?According to Joanna Mauer, the technical advocacy manager for the Appliance Standards Awareness Project, the DOE Btu rating is more accurate than ASHRAE because it considers hot air infiltration and heat losses through the ducts.Mauer said ASHRAE, the manufacturer's Btu, doesn't account for the significant heat released back into the room by the exhaust hose. There also isn't a consistent testing standard.The US Department of Energy (DOE) established standardized testing to account for the heat that ends up back in the room. We reference the DOE ratings in our guide.What can you do if you are stuck with an AC that doesn't have enough Btu to adequately cool a room?Mauer recommended keeping the filter clean. Also, close the curtains and blinds during the day to reduce the room's heat gain. Lastly, she suggested running a fan to circulate the cool air.Which is better: a portable air conditioner or a window/room air conditioner?As we outline in our guide to portable air conditioners vs window air conditioners, window ACs are the better option for most people. In our tests, the most efficient portable AC still used 60% more power than our top window pick. The window unit also cost less and did much better cooling.We strongly recommend buying a window AC if you have a window to support it. Portable units are only preferable when you don't have a single- or double-hung window.Can I use a portable air conditioner in a room without windows?Yes, but the hot air needs a way to leave the space. Otherwise, the unit won't be able to provide any cooling benefits. Your portable AC just needs an opening big enough for the ventilating hose to send the heat outdoors.How do I clean and maintain my portable air conditioner?To keep your portable air conditioner working optimally, you need to clean the filter at least once per month, more if you are using it more. Below are other cleaning tips to ensure you get the most out of your unit.Weekly:Remove condensation: Regularly remove the condensation that builds up from the cooling process. Many portable units make this easy with a built-in dehumidifier or drain hose. When you put the AC away for the season, remove condensation to avoid mold buildup.Keep the hose short: You can improve your portable air conditioner's efficiency and reduce dust and moisture buildup by keeping the hose as short and straight as possible.Wipe the exterior down: Run a damp cloth along the outside of your unit to remove dust.Monthly:Clean the filter: A filter helps reduce allergens in your air and allows for optimal airflow. Follow the manufacturer's recommendations for how often to clean the filter. The best vacuums outfitted with a crevice tool attachment should get the job done. You can also wash the filter with water, but ensure it dries completely before reinstalling it.Check the insulation: To keep your air conditioner running efficiently, check to make sure the insulation remains in place and seals any cracks. If your unit doesn't have foam seals, consider picking up affordable adhesive strips. Apply insulation any time you move the AC.Twice per season:Vacuum the condenser coils: Grab a screwdriver to remove the back panel to access the condenser coils on the back of your unit. To keep your AC running efficiently, use a vacuum with the crevice attachment and run it lightly over the coils. Do not press hard. You don't want to dent the coils.
