EcoFlow WAVE 3 review
EcoFlow WAVE 3 Portable Air Conditioner and Heater
By Tom Calder
The odd one out, and the reason it's here: the WAVE 3 can run from its own optional 1,024Wh battery, so it keeps a small room cool, or warm, through a power cut, and it ducts air in and out through two hoses. It's small, though: 1.8kW on the label, about half a typical 12,000 BTU unit, and EcoFlow sizes it for 11 to 17m². T3 found it loud at higher speeds and saw it leak in automatic drainage mode. Buy it for a bedroom, office, campervan or off-grid space, not a living room.
- Best for
- Cooling or heating a small room off-grid or through a power cut
- Skip it if
- You only want summer cooling for a normal room on mains power
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Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- Runs from an optional battery
- Dual duct, plus a heat pump
- 15.6kg: light for a portable
Worth knowing
- 1.8kW: small rooms only
- Battery adds £500 more
- 65dB(A) label noise
Out of stock when we checked: our alternatives
Closest in size first, then by our score. None of them was showing out of stock when we last checked.
Best for The most cooling of any single-hose unit here
as of 21 Oct 2026, 10:37 BST · Details
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Our review
A compact two-duct heat pump that cools at 1.8kW, heats at 2.0kW, and takes power from an optional 1,024Wh battery of its own, so it is the only unit on our list that works through a power cut or away from a socket. The number that matters is 11 to 17m²: a bedroom, van or cabin, not a living room. It suits households who need one small space kept cool or warm without mains power.
What the numbers mean
EcoFlow's spec sheet gives 1,800W of cooling and 2,000W of heating (6,100 and 6,800 BTU), from rated inputs of 690W and 645W on mains, or 640W and 606W on battery. The EU label fiche for model EF-WA-H01-3 confirms 1.8kW cooling at EER 2.6 (class A) and 2.0kW heating at a COP of 3.1 (class A++), using 0.7kWh an hour to cool and 0.6kWh an hour to heat: on mains, about 18p an hour cooling and 16p heating at the Ofgem price cap unit rate of 26.32p per kWh for October to December 2026. Label sound power is 65dB(A) in both modes; EcoFlow quotes 44 to 58dB, and 44dB in Sleep mode.
In a UK power cut
The add-on battery holds 1,024Wh of lithium iron phosphate cells, and EcoFlow quotes 2 to 8 hours of running on it, the 8 hours in Eco mode in optimal conditions: holding a small, well-insulated room at temperature. For full-power cooling at the 640W rated battery input, our power-station planning method gives a little over an hour, a cautious figure. It can also run from a power station's mains socket at 690W; a 4,096Wh unit such as the DELTA Pro 3 gives about four and a half hours of full cooling by the same method. In a winter cut, use the heat pump on Eco in one closed room as part of a wider power cut plan.
In a British home
EcoFlow sizes it for 11 to 17m², with both insulated ducts running from the back of the unit to the outside. There is no window kit in the UK sense: the box holds the insulated ducting, three adapter covers, a drain pipe and a duct-size template, and a car vent seal comes only in a bundle, so budget for a panel or seal of your own for a house window. Condensate collects in a bottom reservoir; EcoFlow says automatic drainage pumps it out through the drain pipe once about 300 to 400ml has built up; holding the drain button for three seconds starts one by hand. Keep the unit level, EcoFlow adds, or the reservoir can overflow.
How it compares
Against mains-only heat-pump portables it is small. The MeacoCool Pro 9000 CH is 9,000 BTU cooling and 8,100 BTU heating from 1,005W and 940W of input, 24kg, with app control and UK support, for 16 to 26m². The Pro Breeze 4-in-1 12000 BTU nearly doubles the WAVE 3's cooling at 3.5kW and heats at 3.3kW, at 29.5kg. Neither runs without a socket. The WAVE 3 is the choice when the battery, the 15.6kg weight or the two-duct design is the point; see the comparison page.
Living with it
The unit weighs about 15.6kg and the battery 9.7kg. EcoFlow's charging table gives two hours from the mains at 700W, three hours from 400W of solar, as little as 75 minutes with both, and 10.8 hours from a 100W car socket. EcoFlow UK gives 24 months on unit and battery, and uk.ecoflow.com orders can be returned within 30 days of receipt; for a change-of-mind return the buyer pays shipping and a transaction fee. T3's June 2025 review saw a leak in automatic drainage mode, so check the drain set-up before leaving it unattended.
Safety
It holds 112g of R290 (propane), and its label fiche says never to interfere with the refrigerant circuit or dismantle the unit yourself. EcoFlow says to drain it before moving it and to keep it as level as possible in transit, since leftover water can spill from the reservoir. The battery is a lithium pack in the home; our lithium battery fire safety guide covers the basics.
Our verdict
Buy it if you need one small room cooled or heated where mains power is unreliable or absent: a bedroom for someone vulnerable to heat during cuts, or a van or garden office. Buy the battery with it, or feed it from a power station you already own; without stored energy it is a light two-duct heat pump that cools less than an ordinary 9,000 BTU unit. Skip it for a living room on mains, where the Pro Breeze cools nearly twice as much and the Meaco about half as much again.
A researched review, built from the maker's specs, manual and UK listings; facts checked 21 Oct 2026. Sources: EcoFlow UK — WAVE 3 portable air conditioner product page (BTU, modes, battery runtime, charging table); EcoFlow UK shop — WAVE 3 portable air conditioner (specifications, rated inputs, what's in the box, drainage FAQ); EcoFlow — WAVE 3 user manual (online); EPREL — energy label product fiche, ECOFLOW EF-WA-H01-3 (1.8kW cooling, 2.0kW heating, EER 2.6, COP 3.1, 65dB, R290); EcoFlow UK — warranty policy (WAVE 3 and add-on battery, 24 months); EcoFlow UK — refund policy (30 days, return shipping and transaction fee); Ofgem — energy price cap unit rates and standing charges (1 October to 31 December 2026).
Who shouldn't buy this
Don't buy it if you only want summer cooling for a normal room on mains power: a 2.6kW unit cools more for less.
Key specs
| Box rating | 6,100 BTU |
| Rated cooling | 1.8 kW |
| Room size (maker) | 17 m² |
| Type | Dual-duct heat pump, battery option |
| Label noise | 65 dB(A) |
| Heating | Heat pump |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
Questions
How long does the EcoFlow WAVE 3 run on its battery?
EcoFlow quotes 2 to 8 hours on the 1,024Wh add-on battery, the top figure in Eco mode in optimal conditions. Flat out at the 640W rated battery input, our cautious planning method gives a little over an hour.
Does the EcoFlow WAVE 3 need a window kit?
It needs its ducting routed outside, but there is no house window kit in the box, only the ducting, adapter covers and a duct-size template. A car vent seal comes only in a bundle.
Can the EcoFlow WAVE 3 heat a room in winter?
Yes. It is a heat pump labelled at 2.0kW of heating with a COP of 3.1 (class A++), for a room of 11 to 17m², and Automatic mode switches to heating when the temperature drops.
How long does the WAVE 3 battery take to charge?
EcoFlow's table gives two hours from the mains at 700W, three hours from 400W of solar, as little as 75 minutes using both together, and 10.8 hours from a 100W car socket.
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