15K BTU AC on a honda 3KW gen

[Bernese guy]

I have a '25 ORV 21RBS with a 15K BTU Air Conditioning unit. I Hooked my Honda 3KW gen to it and it runs just fine. Fan on low setting. I was told by ORV and dealer that a Honda 3KW would not do it. But It does. How?

[NoviBill]

What is your AC rating in watts or amps? My guess would be around 18 amps. So 18a*120v = 2100 watts - possibly surge to 3000 watts. Sounds like within your generator's capabilities.

[twinboat]

Honda boosted the 2000 output to 2200 for 15k ACs, a 3000 shouldn't have a problem.

[C.Martin]

If you haven't heard about them... a MicroAir Easy Start is a add-on device which significantly reduces LRA (locked rotor amperage). That's the surge required to start the compressor from rest. It goes thru a learning process where it trims the start up amperage draw to a much more tame level...making it easier for smaller gensets to handle. I installed them on both rooftop units...which makes it possible for me to reliably run two units on a 30A shore power connection. It also lets me run my front air conditioner off my Inverter (wiring mod required).

[wildtoad]

I suspect the 3KW will run the AC just fine but not much else at the same time. If you have propane enabled water heater, refrigerator they should work fine. Microwave should be used when AC isn’t running.

I’ve not used one but there is a kit (Soft Start?) you can put on the AC to reduce the surge required to get the unit started. Once running you can use some other low draw devices.

If you want to better enjoy your unit on generator power you might consider swapping for something with more power.

[1stimerveer]

Friends we travel with have harbor freight 3000 watt gennys and run their 15K btu AC units with no problem. But this is its limit.
They just cant run anything else while its in operation.
Safe travels and all the best.

[tpaul]

I can run my 15K AC with my Honda 2200 generator on propane. I also added the Easy Start to my AC and that definitely helps. Don't think you should have any problem with a 3KW generator but would think that an Easy Start or Soft Start would be a good addition. If my 2200 can handle the AC your generator should be able to handle at least an additional 5-700 watts without turning off the AC.

[US1]

Had a 2000W Honda gen that would run the AC on my 1st RV no problem.
Sounds like the knowledge of your ORV dealer is lacking

[C.Martin]

Screenshot of my front 15K Dometic HeatPump. In Heat Mode. Drawing 10.3A running, and 13.4A LRA during last Start-up. 13.4A x 120V = 1608 W

So. with 2000 watts available at 120v...your limitation is around 16.6A. Believe me, the LRA on these units without a MicroAir EasyStart goes way past that. Faults have been due to campgrounds with Brown Out conditions. We had a rolling brownout condition occurring very recently in Cave City KY Mammoth Cave Jellystone Park. Weird thing is, there were only a few RVs in this gigantic campground. Usually brownouts occur when the campground is Full...during the Summer...with everyone running Air Conditioners full blast.

https://www.microair.net/products/ea...e-soft-starter

They offer ones with or without Bluetooth monitoring.

Also consider a bonding plug if using a portable generator...as it may fault your surge protector if you have one...as it may detect an open ground.

[Mudfrog]

Originally Posted by Bernese guy

I have a '25 ORV 21RBS with a 15K BTU Air Conditioning unit. I Hooked my Honda 3KW gen to it and it runs just fine. Fan on low setting. I was told by ORV and dealer that a Honda 3KW would not do it. But It does. How?

To answer your question, no doubt the surge caused at compressor start up puts some strain on the genset. My guess is that the surge is brief enough and/or that your a/c unit has some sort of soft start type device installed on it. Compressor start up is generally when you will have an issue and since you don't, you should be good to go.

This is one of those questions a manufacturer, and especially a dealer, wouldn't know the answer to off the top of their heads.

[C.Martin]

Originally Posted by Bernese guy

I have a '25 ORV 21RBS with a 15K BTU Air Conditioning unit. I Hooked my Honda 3KW gen to it and it runs just fine. Fan on low setting. I was told by ORV and dealer that a Honda 3KW would not do it. But It does. How?

3000w / 120v = 25A

The standalone AC was designed for a 20A branch circuits installation.

So, you have plenty….it would be a matter of managing other loads. Converter/Inverter draw, cannot use electric. Water heater elements, microwave, or be plugging in blow dryers or instant pot.

I believe he was probably trying to say…it isn’t 30A capable and certainly not 50A capable. But, failed to mention that it will work if managed properly. With an Easy Start, you’d even be able to add some more loads. Just need to do some math, or take some amp reading with a clamp meter.

[Bernese guy]

I really go to places with hook ups. I need the AC in an emergency in case I get stranded in a 100F place for my dog. If I could shut everything else off and just run the AC with the Honda 2200 I would be good. I could look for a nice portable gen when I get out of Calif.

[1stimerveer]

You have other options to stay cool. We travel in our Aspen trail 1900 RB camping in 100 deg temps with no problem.

Parking under a shade tree, using a shade cloth with your awning facing west are two simple things to help your ac do the job a little easier. We have a 13,500 btu unit that does the job for us.

We upgraded from a champion 2000w inverter to an Onan 4,500i, that has plenty of power to run the ac and then some. Love it and never looked back

Safe travels and all the best.

[corn18]

Originally Posted by Bernese guy

I have a '25 ORV 21RBS with a 15K BTU Air Conditioning unit. I Hooked my Honda 3KW gen to it and it runs just fine. Fan on low setting. I was told by ORV and dealer that a Honda 3KW would not do it. But It does. How?

It does it by providing enough power to startup and run your air conditioner. ORV and dealer were wrong.


I can run my 15k BTU a/c off my Champion 2200W genset but only with an easy start installed. The a/c draws 16Ain 85 deg weather and my genset provides just enough for that.