≈ 7.7 nights (8h/night) · Safe motor start buffer (99.1% margin).
CPAP machine running (65 W max) and start-up (90 W max) draw fit the Goal Zero Yeti PRO 4000's 3,600 W continuous / 7,200 W surge ratings.
humidifier and heated tube off (15 W)
standard pressure with humidifier active (40 W)
high pressure with HumidAir and heated tube at max (65 W)
Via ResMed Air11 90 W DC/DC Converter (part 39231)
Via ResMed Air11 90 W DC/DC Converter (part 39231)
Via ResMed Air11 90 W DC/DC Converter (part 39231)
≈ 7.7 nights (8h/night)
System standby power: 22W (33.8% of total draw)
Provides 4× CEE 7/3 (230V), 1× IEC Commando (32A) (120V 60Hz).
Pure sine wave inverter output. Safe for sensitive medical electronics and variable-speed motors.
Inductive motor/compressor load with 1.6× starting surge (motor inrush) (99.1% worst-case surge margin).
Wall AC fast charge at up to 1800W (120m to 80%, 150m to 100%).
Safe envelope verified: Starting surge (65W) remains comfortably below the 7200W surge trip line, with steady-state operation settling into the safe continuous zone at 40W.
About 61 hours on AC power, with the CPAP machine averaging 40 W (standard pressure with humidifier active (40 W)). The Goal Zero Yeti PRO 4000 then draws about 65 W from its battery, including 22 W for the inverter itself. Best case: about 4.4 days (humidifier and heated tube off (15 W)). Worst case: about 43 hours (high pressure with HumidAir and heated tube at max (65 W)). At 8 hours a night, that's about 7.7 nights.
Yes. Using the ResMed Air11 90 W DC/DC Converter (part 39231) on the Goal Zero Yeti PRO 4000's 12 V car socket, the CPAP machine runs about 4.3 days instead of 61 hours on AC, 67% longer, because it skips the inverter's conversion loss and its 22 W idle draw. That's 13 nights instead of 7.7 nights.
That simple division gives 4.2 days, but the Goal Zero Yeti PRO 4000's inverter draws about 22 W whenever its AC outlets are on. At this light load that's 34% of everything the battery supplies, and inverter conversion losses take a further share. The idle figure comes from Goal Zero.
On wall power: about 120 minutes to 80% and 150 minutes to full (Goal Zero figures). With its maximum 3,000 W of solar input connected, expect about 2,400 W in full sun, so a full recharge takes roughly 1.8 hours of full sun, so it can refill in a single day with 4 peak sun hours.
It can act as a backup supply: with the CPAP machine plugged into the Goal Zero Yeti PRO 4000 and the Goal Zero Yeti PRO 4000 plugged into the wall, it switches the CPAP machine to battery in about 10 ms when the grid fails (Goal Zero calls this UPS mode).
Statutory 30-day retail price announcements & rate revisions
Bord Gáis Energy winter rate adjustment: +1.60c/kWh Day, +0.90c/kWh Boost (2am–5am), and +€12.50/yr standing charge effective 20 Nov 2026.
Energia retail revision: +1.85c/kWh Day, +1.15c/kWh EV Boost (2am–6am), and +€14.20/yr standing charge effective 15 Nov 2026.
Dual Fuel Day Night: Day -4.64c/kWh, Night -3.25c/kWh (effective 2026-11-05)
Electricity Day Night: Day -4.64c/kWh, Night -3.25c/kWh (effective 2026-11-05)
SSE Airtricity statutory price cut: -1.25c/kWh Day, -0.65c/kWh Night, and -€8.40/yr standing charge effective 01 Oct 2026.
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