How long can the EcoFlow DELTA Pro Ultra run a Central AC (3 ton)?
3 hours
Formula: (6.1kWh × 0.85 inverter efficiency) ÷ 42 kWh/day = 3 hours. At continuous 3500 W draw (no duty cycle), about 1.5 hours.
What if you add a battery? The + Extra Battery config jumps to 12.3kWh — roughly 6 hours on a Central AC (3 ton).
Appliance
Central AC (3 ton) · 3500 W / 8000 W surge · 240V
Battery (base)
6.1kWh · 7.2kW / 10.8kW surge
Some links may be affiliate links. GridMatch may earn a commission if you buy through them, at no extra cost to you.
Runtime Quick-Check
Runtime Quick-Check
Pick a battery and an appliance — see days of runtime after the 0.85 inverter derate.
3 hours
Formula: (6144 Wh × 0.85) ÷ 42 kWh/day = 3 hours. Continuous draw ≈ 1.5 hours at full load.
Nearest alternatives
Running more than one device?
Open sizing wizard