Which is better for running an RV air conditioner?

The FlexPower 4500ies gives 3600 W continuous, which covers most 13,500 BTU RV air conditioners with a soft-start kit. The WEN drops to 3150 W continuous on propane, so run it on gasoline for the full load.

Is the WEN worth the extra $30.99?

Yes if you want propane operation, the fuel shut-off valve and the three-year warranty. If you only burn gasoline, the FlexPower gives more running watts for less money.

Which one is quieter?

The WEN is rated 58 dBA at quarter load at 22 feet. The FlexPower is rated under 63 dB. Both are quiet enough for campgrounds with quiet hours.

Which is easier to move?

The FlexPower at 82 lb with a telescoping handle and wheels. The WEN is 100 lb but also has onboard wheels and a handle.

Can either one be paralleled with a second unit?

The FlexPower 4500ies is listed as parallel ready. WEN sells parallel kits for some models, but check the DF451i manual before buying a second unit.

Both use air-cooled OHV engines around 212 to 224cc. The WEN's fuel shut-off helps prevent carburetor gumming during storage, which is a common cause of small-engine failure.

FlexPower 4500ies Quiet Inverter Generator with Electric Start vs WEN DF451i Dual Fuel Inverter Generator

Buy the FlexPower 4500ies for more running watts, less weight and a lower price. Buy the WEN DF451i if you want to run on propane as well as gasoline. The FlexPower is $849.00 at FactoryPure as of November 5, 2026. The WEN is $879.99 at Walmart as of November 5, 2026.

Today the FlexPower 4500ies Quiet Inverter Generator with Electric Start costs $30.99 less at its best price.

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