Many parts of the US are sizzling right now, unable to escape the extreme heat alerts constantly flashing on the news and our phones. I regularly experienced triple-digit temperatures while living near the desert for ten years. But there’s a big difference between that and the 100+ temperatures with humidity levels above 60% many of us are currently experiencing on the East Coast. 

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Like many unlucky Americans, one of the two overworked air conditioner units left us hanging during the latest heat wave. HVAC repair companies are swamped with service requests, and we were struggling, so I pulled out the EcoFlow Wave 3.

This portable unit is an upgrade from its predecessor, the Wave 2, and features Auto, Dehumidify, Sleep, and Pet modes. Aside from being relatively heavy (over 50 lb when you add a battery), the Wave 3 is easy to set up and connect to the EcoFlow mobile app. The device uses Wi-Fi and Bluetooth to connect to your phone, which you can then use as a remote control and to adjust settings, giving you an extra layer of convenience. 

I’ve been testing the EcoFlow Wave 3 sporadically for a few weeks, but began using it more religiously after the summer heat rolled around. 

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My husband’s home office is well-insulated and soundproof, but it’s an addition that wasn’t properly incorporated into the home’s existing HVAC system and doesn’t have any windows. As a result, it gets very hot in summer and very cold in the winter. 

This room turned out to be a great place to test the Wave 3 once the dog days of summer began. By routing the exhaust vent through an existing opening built into a wall to route cords, the Wave 3 successfully lowered the temperature by almost 20 degrees in under an hour. 

It maintained the set temperature for as long as the device was powered on. The battery lasted a couple of hours when used in Max mode, which is the highest setting, but you can stretch it to up to eight hours when you use it in Eco mode.

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I found the EcoFlow Wave 3 best suited for insulated areas over tents and places not built adequately for climate control. It’s a helpful comfort measure, but one you shouldn’t rely on for safety.

The Wave 3 is more powerful than its predecessor, but it isn’t meant to replace a full-size air conditioning unit. It features 6,100 BTU for cooling and 6,800 BTU for heating, which is about half the capacity of a wall-mounted unit that costs around a third of the price. So you’re paying extra for the convenience of portability of the Wave 3, especially when paired with a battery and portable solar panels. 

Whether that convenience is worth the price hinges mainly on the individual use case. 

Once our upstairs A/C quit in the middle of a heat wave, I had to repurpose the Wave 3 from a testing unit to cool down my kids’ playroom during the day and a bedroom at night. The top floor, where the heat concentrates during summer, reached up to 93 degrees, with the outdoor temperature at 102 degrees. 

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My kids are home for summer break, and they love spending time in their playroom, which has all their toys, craft supplies, and a TV, but they couldn’t do it when it was 90 degrees there. I decided to set up the Wave 3 on a table in the playroom and cut out a piece of foam for the window using the stencil included with the unit.

I then routed the inlet and exhaust ducts through the piece of foam and ran the Wave 3 to bring the room’s temperature from 86 to 75 degrees. The inlet duct pulls the fresh outside air, while the exhaust vents the hot air from the cooling process. I also ran the drain line out the window to release the water collected during condensation. 

Admittedly, the Wave 3 struggled to cool down the room efficiently multiple times. For example, it brought the temperature down to 82 degrees in under 20 minutes on one occasion, but then it took over an hour to get to 78. The unit then maintained that temp, even if set to 75. At this time, the outdoor temperature was 96 degrees, with the midday sun shining down on the window next to the Wave 3. 

This and other tests made me realize that the Wave 3’s cooling capability is limited under extreme conditions, like heat waves. I look forward to seeing how the heating performs during the winter months. 

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Even so, 78 degrees is much more comfortable for my kids, especially while they were all in the room with the Wave 3. They dove into setting up racetracks and doing crafts, leaving my husband and me able to work uninterrupted.

Because of this, I wouldn’t rely on the Pet mode advertised by EcoFlow to keep your pets safe in a hot car. This Pet mode is meant for when you have your Wave 3 and your pet in your vehicle, and you have to leave your furry friend behind. When the EF Wave 3 detects a temperature of 77 degrees or higher, it begins cooling to prevent your pet from overheating. 

ZDNET’s buying advice

The EcoFlow Wave 3 is built for off-grid adventurers, whether van lifers, RVers, boaters, or tiny home dwellers. However, it isn’t meant to be a device you reach for in emergencies. Its performance is limited in extreme conditions, so I’d recommend it to make trips more comfortable, not to prevent heat stroke or hypothermia.

It’s a practical device, with improved performance over the Wave 2 and the ability to charge it using solar energy, but it is also pretty expensive. It’s effective in up to around 175 square feet but can struggle in larger areas.