If your summers are dry, an evaporative cooler cools a room on about 75 watts. If they're humid, you need a portable air conditioner, which pulls both heat and moisture out of the room. Here's how to tell which one fits your home.
The short answer
Your climate decides it, then your room size.
• Dry heat (Phoenix, Las Vegas, Tucson, El Paso, inland California): an evaporative cooler. It works best when indoor humidity is below roughly 50%, uses a fraction of the power and needs no installation.
• Humid heat (the Southeast, Gulf Coast, Midwest summers): a portable air conditioner. In damp air an evaporative cooler mostly adds moisture, while an AC removes it.
• Not sure? Check your local humidity on a typical hot afternoon. If it's usually under 50%, the cooler is the cheaper, simpler choice.
How each one cools
An evaporative cooler pulls warm air through water-soaked pads. As the water evaporates it absorbs heat, so the air coming out is cooler and a little more humid. It's the same effect as a breeze after a swim. There's no compressor, just a fan and a small pump, so it runs on very little power. You refill the water tank, and it needs a slightly open window or door so the moist air can escape.
A portable air conditioner works like a window unit on wheels. A compressor pulls heat and moisture out of the room's air and pushes the heat outside through an exhaust hose in a window. It cools regardless of humidity and dries the air too, but it uses far more power, it's heavier, and it needs that window connection.
Neither one is "better". They solve different problems. An evaporative cooler is not an air conditioner, and in humid weather it can't do an AC's job.
Side by side
Figures come from the products we carry. Other models will differ.
|
|
Evaporative cooler |
Portable air conditioner |
|
Works best in |
Dry heat, humidity under ~50% |
Any climate, including humid |
|
Effect on humidity |
Adds moisture |
Removes moisture |
|
Power use |
60–75 W |
About 1,120 W (9,000 BTU model) |
|
Weight |
10–13.4 lb |
47.5 lb (9,000 BTU model) |
|
Noise (rated) |
60 dBA (550 sq ft model) |
52–56 dB |
|
Setup |
Plug in, fill the tank, crack a window |
Exhaust hose through a window kit |
|
Ongoing care |
Refill water, rinse pads |
Clean filter, drain collected water |
|
Room size |
Up to 550 sq ft |
Up to 250–400 sq ft |
|
Price at AC-Now |
$99–$144 |
$399 |
One surprise: an evaporative cooler isn't automatically quieter. Its fan moves a lot of air, so check the noise rating if it's going in a bedroom.
Which one fits your space
A home office or small bedroom in dry heat
Best for: one person, one room, no installation.
The Portable Evaporative Air Cooler – 256 CFM, 4L Tank ($99) has a 4-liter tank, moves 256 CFM, draws 75 W and has a timer of up to 8 hours. At 10 lb it's easy to move from desk to bedside. The small tank means more frequent refills on long, hot days.
A living room or open-plan space in dry heat
Best for: larger rooms up to 550 sq ft.
The Portable Evaporative Air Cooler – 550 Sq Ft ($144.22) has a 5-gallon tank for long runs between refills, moves 1,400 CFM and uses just 60 W. It's rated at 60 dBA, so it's better suited to living spaces than a light sleeper's bedroom.
A bedroom in humid summers
Best for: rooms up to 250 sq ft where you need real cooling and drier air.
The 9000 BTU Portable Air Conditioner – 3-in-1 ($399) cools, dehumidifies and runs as a fan. It's rated at 56 dB and takes up a 12.5 × 14 inch footprint.
A bigger room, or one you also want to heat
Best for: rooms up to 400 sq ft, used year-round.
The Uhome 12,000 BTU Portable Air Conditioner & Heater ($399) covers more space than the 9,000 BTU model at the same price, adds a heat mode for cooler months, and is rated at about 52 dB. If you're unsure between the two ACs, this is the one most people should pick.
The patio or backyard
Best for: outdoor seating in dry heat.
Neither indoor option is made for outside. The 16-Inch Outdoor Misting Pedestal Fan ($199) moves 2,120 CFM with three mist levels, connects to a garden hose, and is ETL certified with a GFCI safety plug.
If your AC's window kit doesn't fit
Most portable ACs include a window kit, but it won't fit every window. The Universal Portable AC Window Vent Kit ($49.99) adjusts from 17 to 65 inches for vertical or horizontal windows. It fits 5.9-inch exhaust hoses, so check your unit's hose diameter first.
Get the most from either one
Evaporative cooler
• Open a window or door a few inches on the far side of the room. Moving air carries the extra humidity out, and the cooling stays strong.
• Start with cold water on hot afternoons.
• Point it at where you sit, not at a wall. It cools people more than it cools the whole room.
• Empty the tank and rinse the pads every few days so they stay fresh.
Portable air conditioner
• Keep the exhaust hose as short and straight as you can. Long loops let heat leak back into the room.
• Seal the gaps around the window kit. Every gap lets hot air back in.
• Close the door to the room you're cooling.
• Clean the filter every couple of weeks and drain collected water as the manual describes.
Ready for the next heat wave?
The best time to choose is before the heat arrives, when you can set up and test without rushing. Browse our full cooling range, or start with the pick above that matches your room and your climate.
