You MAY be able to get your AC to start up with either a "Easy/ Start RV AC Capacitor" (Search E-Bay, Amazon, or the general internet).
These are also called Hard Start or Soft Start.
I was able to get my 3100 watt Champion Generator to start the 15K BTU AC by turning off the breakers to EVERYTHING ELSE in the trailer besides the AC, starting up the AC, then turning on the minimum of other needed electrical stuff after the AC started. The AC needs about 12-13 amps to run, but a LOT to start. I have yet to install an Easy Start capacitor. I RARELY run on generator, only when power is lost at the RV park.
Well, after being connected to my Dometic Brisk Air II for about 2 years, my $300 Model 364 Easy Start box has begun to work intermittently in starting the air conditioning compressor. This is more of a problem because the noisy blower starts, but you often don't notice that the low rumble of the compressor is missing, and no cooling. It looks like the Easy Start Box only has a 1 year warranty. I got the installation instructions, figured out a removal wiring process that gets the system back to original wiring, removed the box, and stopped the problem.
It is starting to get warm in Southern California, although this as late for summer warming as I can remember here. Lots of 100+ degree days in April and through late September in my youth. Fire season preventative power shutoffs are probable in the rural areas the RV parks I use are in, and now the looming undercapacity of the California electric grid is in the near future, so I expect be using my generator (which soon you won't be able to legally buy new in California) as needed.
In doing a Google search for prices and alternatives, I noticed that Dometic has come out with their own soft start add-on box that plugs into their wiring connectors with a minimum of other wiring modifications. It costs about the same as all the others ($300). Has anybody used this Dometic product? What are the recommendations on the best soft start boxes, including reliability.
Here's the Google search with all of the products:
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