How long can the Anker SOLIX F3800 run a CPAP machine?
10.2 dayswell beyond what you asked for
Formula: (3.8kWh × 0.85 inverter efficiency) ÷ 0.32 kWh/day = 10.2 days. At continuous 40 W draw (no duty cycle), about 3.4 days.
What if you add a battery? The + Home Backup Kit config jumps to 7.7kWh — roughly 20.4 days on a CPAP machine.
Appliance
CPAP machine · 40 W / 60 W surge
Battery (base)
3.8kWh · 6kW / 9kW surge
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Runtime Quick-Check
Runtime Quick-Check
Pick a battery and an appliance — see days of runtime after the 0.85 inverter derate.
10.2 days
Formula: (3840 Wh × 0.85) ÷ 0.32 kWh/day = 10.2 days. Continuous draw ≈ 3.4 days at full load.
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