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JoeChiOhki's avatar
JoeChiOhki
Explorer II
Aug 07, 2019

Experiences with Onan Portable Gas Electric Generators

While I was searching for something, I stumbled across an Inverter Generator that Onan is manufacturing, the P4500i.

It's a four stroke, gasoline powered inverter generator, rated at 3700watts continuous, 4200 watts peak and like the smaller 2000 watt units, can be paralleled.

Onan P4500i Spec Sheet

RV Parts Country has a demo video of one of these, but they never put it under any load, so the noise level measurements probably can be called into question.

P4500i Demo Video

From most of the places I've seen pre-ordering/backordering for this, its going for around a $1000, which is considerably less than comparable 4000 watt Hondas or Yamahas.

I'm wondering if anyone here has any experience with Onan's already existing portable Inverter Generators and how their real world performance / quality holds up.
  • Install a MicroAir on your AC and get a Honda 2200i to run it.
  • Kayteg1 wrote:
    My Honda 3000 starts even 15k AC on ECO mode and that's with charging and like 150W Water heater element on.
    Than I hear more and more that adding easy start to AC makes it running on 2000W quite possible.
    So even there is nothing wrong with having bigger generator, where are you going to carry it?
    Than I drove via Oregon twice this summer. Never run generator in the state.


    Same place I am currently carrying the 4200 watt non-inverter that I use for our home, on the rear basket. I'm currently looking to improve the basket design to make it easy to lift and lower, but I may not need that with the much lighter inverter unit, our current generator weights well over a 100lbs and is a royal pita to shift around, even with the wheels on it, which is why I was debating designing a drop basket with an electric motor on it like a scooter lift.

    I usually tend to go east into the desert country when I travel, so being able to keep the house cooled when its 90-110 degrees out is a must, especially with pets onboard.

    Oregon is only cool and comfy in a small part of the state during the summer months, and that's mostly the coast line, the central mountains and east are alot warmer (a good portion of it is scrub desert), plus on our longer trips we do alot of wallydocking / urban boondocking where having sufficient power is a necessity in some cases to run the A/C along with microwave, or other appliances at the same time.

    Our camper also doubles as a dressing studio periodically when we're at costumed events where power is not available, and nor are changing studios and larger draw items like curling irons and what not are used simultaneously. We have some outfits that take 3-4 hours worth of makeup and hair work to get into for the events.
  • My Honda 3000 starts even 15k AC on ECO mode and that's with charging and like 150W Water heater element on.
    Than I hear more and more that adding easy start to AC makes it running on 2000W quite possible.
    So even there is nothing wrong with having bigger generator, where are you going to carry it?
    Than I drove via Oregon twice this summer. Never run generator in the state.
  • Kayteg1 wrote:
    Do you have dual AC on your TC to need 4200 Watts?
    Not likely smart TC owner would buy one, but I would post in TT and ClassA sections.
    Also check Costco. Traveling via few states and provinces, I have seen quite a selection of generators at Costco.
    Some of them dual-fuel, what is the way to go if you want generator for TC and also back up for your home.


    The bulk majority of standard RV A/Cs will not start on a 2000 watt generator without tapping it out to the max, leaving little extra power. Alot of folks here, just buy two 2000 watt generators and team them together.

    The running wattage is 3700 watts, which is a basic 30 amp service. 4500 watts is peak/surge, not a sustainable load rating.

    In the case of my unit's A/C, which is a Duo Therm Brisk Air II 13500 BTU Rated unit, the recommend generator rating is 3.5kw.
  • Do you have dual AC on your TC to need 4200 Watts?
    Not likely smart TC owner would buy one, but I would post in TT and ClassA sections.
    Also check Costco. Traveling via few states and provinces, I have seen quite a selection of generators at Costco.
    Some of them dual-fuel, what is the way to go if you want generator for TC and also back up for your home.
  • I don't believe that Cummins/Onan make ANY of their small generators ! Eveb the small diesel are made by someone else in Germany.

    That model is a rebranded Ducar D4000is
  • An Onan priced that low is made in China and no better or worse than the other offshore units. Just sayin'