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Will it run?

Will a 5,000W generator run a window AC unit?

Yes about 1,260W to spare

Running window ac (12k btu), refrigerator, household lights (led) on a 5,000W generator: the steady draw is 1,660W, but it peaks at 3,740W when the window ac (12k btu) starts.

LoadRunningStarting
Window AC (12k BTU)1300W3380W
Refrigerator160W480W
Household lights (LED)200W200W

Why the peak is what matters

A generator doesn't stall on the running total — it stalls on the surge. The single largest startup spike here comes from the window ac (12k btu). Add it to the running load of everything else and you get a 3,740W peak. Since that is under 5,000W, the generator handles it.

Size your exact setup

This covers a typical load set. Your actual appliances will differ — size your real situation in the calculator:

Common questions

Will a 5,000W generator run a window AC unit?

Yes. Running window ac (12k btu), refrigerator, household lights (led) draws 1,660W continuously, but peaks at 3,740W when the window ac (12k btu) starts. A 5,000W generator covers that with room to spare.

What's the difference between running and starting watts?

Running watts is the steady draw; starting (surge) watts is the brief spike when a motor starts. Generators must handle the surge, not just the running total — that's why this calculation matters.

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