How long will the EcoFlow DELTA Pro 3 run a window AC 5,000 BTU?

About 15 hours from a full charge. A window AC 5,000 BTU averages about 225 W (450 W running, on about 50% of the time), and the 4,096 Wh battery gives about 3,482 Wh after inverter losses. That is 6.5% of the battery an hour.

Will the EcoFlow DELTA Pro 3 start a window AC 5,000 BTU?

Yes. It needs about 1,350 W for a moment when the compressor starts, and the EcoFlow DELTA Pro 3 is rated for 8,000 W surge, 5.9 times that. Avoid starting other motors at the same moment.

How many days of normal use is that?

About 1 day, if you use a window AC 5,000 BTU about 8 hours a day and nothing else is plugged in.

EcoFlow · Will it run?

Can the EcoFlow DELTA Pro 3 run a window AC 5,000 BTU?

Published October 15, 2026

Short answerYes

Yes. The EcoFlow DELTA Pro 3 runs a window AC 5,000 BTU for about 15 hours from a full charge. It needs about 1,350 W for a moment when the compressor starts, well within the 8,000 W surge rating, then about 450 W while running against 4,000 W continuous.

Add your other devices

Key numbers

Runtime: 15 hrs; from a full charge
Battery used per hour: 6.5%; at 225 W average

Window AC 5,000 BTU

Running: 450 W; 400–550 W range
Start-up: 1,350 W
Average: 225 W; on 50% of the time

EcoFlow DELTA Pro 3

Battery: 4,096 Wh; about 3,482 Wh usable
Output: 4,000 W; continuous
Surge: 8,000 W; start-up peak

How we worked it out: 4,096 Wh × 0.85 ÷ 225 W average (450 W × 0.5 duty) = about 15 hours. The 0.85 covers inverter and battery losses. We do not test units ourselves; the numbers come from the official spec sheets and typical device draws. How we pick

EcoFlow DELTA Pro 3

4,096 Wh · 4,000 W output · 8,000 W surge · 113.5 lb

Full specs and runtimes

Check price on Amazon Check price at EcoFlow

We may earn a commission if you buy through these links. It doesn’t change your price. How we make money

What else the EcoFlow DELTA Pro 3 runs

One device at a time, from a full charge.

Other power stations for a window AC 5,000 BTU

The nearest sizes that also run it.

Keep going

Real runtime depends on the model you own, room temperature and battery age. The 15 hours above is an estimate, not a measured result.

Common questions

How long will the EcoFlow DELTA Pro 3 run a window AC 5,000 BTU?: About 15 hours from a full charge. A window AC 5,000 BTU averages about 225 W (450 W running, on about 50% of the time), and the 4,096 Wh battery gives about 3,482 Wh after inverter losses. That is 6.5% of the battery an hour.
Will the EcoFlow DELTA Pro 3 start a window AC 5,000 BTU?: Yes. It needs about 1,350 W for a moment when the compressor starts, and the EcoFlow DELTA Pro 3 is rated for 8,000 W surge, 5.9 times that. Avoid starting other motors at the same moment.
How many days of normal use is that?: About 1 day, if you use a window AC 5,000 BTU about 8 hours a day and nothing else is plugged in.