Buy too small and your air conditioner won't start. Buy too big and you haul extra weight and burn extra fuel. Here's how to land in the middle.
Start with your RV's amp rating
Look at your shore power plug. A 30-amp RV can draw up to 3,600 watts (30 amps × 120 volts). A 50-amp RV uses two 50-amp legs and can draw up to 12,000 watts, though few rigs ever use that much.
Add up what you'll actually run
Lights, a fridge, a TV and phone chargers need far less than the maximum. The air conditioner is the big one. It needs a burst of extra power, called starting watts, for a second or two when the compressor kicks on.
Our rule of thumb
- No A/C, just the basics: about 2,000 to 2,200 watts. A Honda EU2200i is quiet and light.
- One rooftop A/C on a 30-amp RV: about 3,500 watts or more, like the WEN 56360i or Champion 4,000-watt dual fuel.
- Two A/Cs or a 50-amp rig: 5,000 watts or more, or two inverter generators linked with a parallel kit.
A soft-start kit on your A/C lowers the starting surge, so a smaller generator can sometimes handle it.
Want silence?
A solar generator makes no noise or fumes, but it stores less power, so it suits light loads.
Compare every pick in our RV Generator Buying Guide.
