How many watts does a Window AC (5,000 BTU) use?

A Window AC (5,000 BTU) draws 600 watts continuously once it's running, but its motor needs a brief surge of up to 1,800 watts to start. A generator has to cover that starting surge, not just the running load, or the motor won't start. Starting watts here is a manufacturer marketing figure, not a real nameplate locked-rotor-amp (LRA) rating — cord-connected room ACs this size are exempt from LRA labeling under UL 484, so no true nameplate surge figure exists for this class. Treat it as a rough estimate.

Running it 8 hours/day costs roughly $24.48/month at the U.S. average residential rate (~$0.17/kWh, early 2026, per the EIA) — real rates vary a lot by state and utility. Use your own rate in the House calculator →

Generators that can run this

• Generac GP2200i
  1,700 W run · 2,200 W start · ~$550
• Champion 2000-Watt Inverter (100692)
  1,700 W run · 2,000 W start · ~$450
• Honda EU2200i
  1,800 W run · 2,200 W start · ~$1,150

Prices as of July 2026 — check the current listing before buying.