I’ve been testing the EcoFlow Wave 3, a follow-up to the all-in-one battery-powered air conditioner, heater, and fan I reviewed last summer. EcoFlow has dialed back its absurd marketing with a more powerful unit that can be recharged through several methods, including the sun. Only now it can automatically (try to) maintain a set temperature range and act as a dedicated dehumidifier, too.

I was grateful to have EcoFlow’s Wave 2 with me last summer while vanlifing around Portugal and Spain. That less powerful A/C helped to offset daytime temps hitting 37 degrees Celsius (98.6 degree Fahrenheit) and made 25C (77F) nights comfortable enough to sleep. But it only worked in small spaces and under just the right circumstances.

The third-generation portable heat pump from EcoFlow can’t perform miracles. We’re still only talking 6100BTU (1800W) of cooling and 6800BTU (2000W) of heating. And placement is limited by bulky intake and exhaust hoses, and the space needed for a receptacle to collect any drained water.

But if you own a van, surf shack, work shed, roof-top tent, boat, or another small space requiring occasional temperature control, then the Wave 3 could be for you. Prices are discounted for a limited time to $849, or $1,399 with the battery bundle, before they rise significantly next month.

While the Wave 2 was limited to spaces smaller than 10 square meters (107 square feet), the Wave 3 is designed to work in spaces up to 17 square meters (180 square feet). To test the claim, I used the Wave 3 as a heater inside a 14.8 square meter (161 square feet) tiny home about the size of a shipping container, and as an A/C inside a 9 square meter (97 square feet) Class-B Sprinter van. The Wave 3 has built-in Wi-Fi (and Bluetooth), so I could connect it to my Starlink Mini and manage operation remotely over the excellent EcoFlow app.

As a heater in a one-room tiny home, the Wave 3 could only just cope with the space, but was a marked improvement over the Wave 2. With temperatures ranging from 8C (46F) to 10C (50F) outside, the Wave 3 at maximum heat could maintain temperatures inside at around 14C (57F) to 17 C (63F). I got 13 hours of runtime off the optional 1024Wh LFP battery using a mix of Eco and Sleep modes starting in the evening and running through the night. The heat was weak, but it was the difference between needing one down-filled duvet instead of two.

In Sleep mode — the lowest setting — the Wave 3 is relatively quiet at around 45dB when measured from a distance of one meter. The sound becomes exhausting at Eco or above, reaching 60dB in Max mode, making it much louder than the 53dB I measured from the Wave 2. It also makes a steady 36dB buzzing sound when charging before falling silent after the battery is full.

After reviewing its predecessor, I already had a good idea of how well the more powerful Wave 3 would cool my van during the day (mixed) and at night (good). It performed as I expected, but I still hoped for more.

Like the Wave 2, the new EcoFlow Wave 3 is helpless to cool the interior of my van when parked in direct sunlight, even with insulated sun reflectors installed in the windows. There’s too much heat produced by all that glass and steel to keep it from seeping into the interior, even in Northern Europe in April.

On one sunny afternoon when the outside temperature never exceeded 18C (64F), I shut all the doors and windows, put the reflectors in place, and cranked the Wave 3 up to maximum cooling. Instead of decreasing the interior temperature, it rose from 24C (75F) to 28C (82F) over a period of 90 minutes before I called it quits. To keep my van cool in those situations, I’d have to permanently install a high-capacity (and more expensive) rooftop A/C on my van. Fine, I expected this result, and EcoFlow is clearer about the limitation this time.

I strongly advise pet owners not to rely on the Wave 3’s new Pet Mode. While it might add a few minutes of comfort to your animal, the Wave 3 can not keep them safe in a sunny parking lot.

As expected, the Wave 3 did much better when I parked in the shade. On a slightly warmer 19C (66F) afternoon, the Wave 3 brought the internal temps down to 16C (61F) — the unit’s lowest setting — and maintained it. So, like the Wave 2, I expect the Wave 3 would keep me comfortable in my van at night even when outside temps were 25C (77F) or even a little higher.

When running off the battery in Max cooling, the Wave 3 died after almost three hours of operation. The 8-hour runtime EcoFlow claims is only for the less powerful Eco mode.

I didn’t stress-test the dehumidifier. I mean, it works, and it can be useful to prevent mold from growing in an RV when parked in storage during the off-season, for example. That can help maximize your value for money by making the Wave 3 useful year-round.

The EcoFlow Wave’s dual-use heating and cooling portability and BTUs per square inch have always set it apart from competitors. The third-generation Wave 3 takes a successful formula and improves on it, without the unrealistic marketing hype that created confusion and disappointment from buyers of the Wave 1 and Wave 2.

But EcoFlow’s Wave 3 heat pump remains a niche product for anyone who need to occasionally heat or cool small spaces in temperate climates, especially if they’re located off the grid.

Pricing for the Wave 3 is a mess due to EcoFlow’s insistence on using limited-time coupons to goose purchasing. At the time of publication, you can buy the Wave 3 without the battery for $849 ($799 with coupon), but then you miss out on the solar charging and portability. Most would be better off with the Wave 3 plus battery combo, currently discounted to $1,399, before increasing to its full list price of $2,198 after May 25th. And while EcoFlow typically offers steep discounts on its Chinese-manufactured products throughout the year, those could be Trumped by tariffs moving forward.

Photos by Thomas Ricker / The Verge