Predator 3500 Inverter

Harbor Freight's cult favorite for RV air conditioners.

Specs

Figures are the manufacturer's published specs; dashes mean the maker doesn't publish a number. Verify against the current datasheet before you buy.

What can it actually run?

Checked with the same math as our calculator: total running watts, plus the single largest motor surge on top. “Tight” means it technically fits but the load sits above 80% of rated output — fine briefly, not where you want to live.

• Fridge, Wi-Fi, and lights

  730 W running · 2,230 W peak
  ✓ runs it
• Storm essentials (fridge, freezer, furnace fan, sump pump)

  3,080 W running · 4,670 W peak
  ✗ too much
• Essentials plus a 10,000 BTU window AC

  4,280 W running · 6,680 W peak
  ✗ too much
• Most of the house (well pump, central AC, laundry)

  13,680 W running · 35,930 W peak
  ✗ too much

The installer's take

The RV crowd adopted this thing en masse because it starts a 13,500 BTU rooftop AC, runs quiet enough for a campground, and Harbor Freight coupons used to make it absurdly cheap. It's heavy for its class and the warranty path is 'bring it back to the store,' but the track record across thousands of RV forum owners holds up. Buy the wheel kit — at 99 lb you're not carrying it far.

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