Every check passes: 923 W running against 4,000 W continuous, and 6,900 W at start-up inside a 8,000 W ceiling. What this page will not do is turn a nameplate watt-hour rating into hours — see the evidence below for why.
official · verified 2026-08-01 · EU 230 V unit × window air conditioner
Nominal capacity4,096 Wh
Surge headroom1.2×
Two numbers decide this, and readers arrive using them interchangeably. Watts are the ceiling on what the inverter can hold at any instant — a window air conditioner needs 923 W of them while it runs, and 6,900 W for the instant it starts. Watt-hours are how much energy the battery holds, and the EcoFlow DELTA Pro 3 holds 4,096 Wh of them on the nameplate. A machine can have plenty of one and not enough of the other.
The verdict above is a calculation — running watts, start-up inrush and inverter waveform against this machine's continuous output and surge ceiling — not a lookup. What it will not do is print a runtime, and the reason is specific: this load’s running watts and its duty cycle are not commensurable, so their product is not an average power and will not be printed as one.
Where those numbers come from
Every figure below carries the tier it came from and the date it was checked. A blank is never
left blank: a field the manufacturer does not publish says so, and a field whose sources
disagree — two documents, or one document with itself — says that instead of picking one.
No usable-capacity figure for this machine
EcoFlow publishes a nameplate watt-hour number and nothing about depth of discharge or inverter efficiency for this model. Dividing the nameplate by this load would be wrong by 20–35% in the flattering direction, so this page shows the nameplate for what it is and refuses to turn it into hours.
Missing: station.usable_capacity_wh
Energy rate instead of a runtime
923 Wh per hourwhile it is actually running
This is the draw while the machine is running and it is deliberately NOT averaged over a duty cycle: for this load the two figures are not commensurable, so their product is not a real quantity. This number multiplies nothing, which is why it survives.
What a window air conditioner demands
Running power923 W Official spec · verified 2026-08-01 · medium confidence
Start-up demand6,900 W Official spec · verified 2026-08-01 · medium confidence
The engine checked 6,900 W — where a record publishes both an absolute inrush and a multiple of running power, the more demanding of the two is used rather than the flattering one.
Start-up duration200 ms Official spec · verified 2026-08-01 · low confidence
Duty cycle18% Official spec · verified 2026-08-01 · medium confidence
Recorded, but deliberately not multiplied by the running watts on this site: the two figures come from sources measuring different things, and their product describes nothing while looking exactly as confident as one that does.
The start-up figure is the manufacturer’s own locked-rotor rating, off a spec sheet for a real model in this class — not a category multiple. Where a standards table and the nameplate disagree, this library uses the nameplate: the standards figure is a selection envelope for breakers and controllers, and sizing a battery to it over-specifies the machine by two to four times.
What the EcoFlow DELTA Pro 3 offers
Continuous output4,000 W Official spec · verified 2026-08-01 · high confidence
Surge ceiling8,000 W Official spec · verified 2026-08-01 · high confidence
Nominal capacity4,096 Wh Official spec · verified 2026-08-01 · high confidence
Inverter waveformPure sine wave Official spec · verified 2026-08-01 · high confidence
Will an EcoFlow DELTA Pro 3 run a window air conditioner?
Yes. 923 W of running draw against 4,000 W of continuous output — 23% of it, with 6,900 W demanded at start-up against a 8,000 W ceiling. The verdict is computed from running watts, start-up inrush and inverter waveform — the working is in the evidence section above.
How long will an EcoFlow DELTA Pro 3 run a window air conditioner?
Not in hours. Hours need an average power, and an average power needs this load's running watts and its duty cycle to describe the same thing — someone checked, and for this load they do not. Multiplying them produces a number that describes nothing. The draw while it is actually running is on the page instead; it multiplies nothing and it is the figure to size against.
Why is there no runtime on a page that says yes?
Because "yes it runs it" and "yes for this long" are two different claims with two different evidence requirements, and this machine only supports the first. The verdict needs a continuous rating and a surge ceiling, which EcoFlow publishes. Hours need a usable-capacity figure, which it does not. Twenty of the twenty-six machines in our library are in that position, and the alternative — nameplate watt-hours divided by label watts — is the single most common wrong number on this topic.