Hello, the peak output of the xg8000 Generac is 10,000 watts, 8,0000 claimed for short term peaks of a hour or so, and I would run it at no more than 6,000 watts, 15,000 btu RV type AC units draw 2,200 watts when running on a 95F day, the unit will draw more than that on a 105F day. So that 2 of those AC units will draw about 5,000 watts on the typical 100F day.
Starting current however is about 3 times the running watts, that surge lasts about 3 seconds, your generator must be able to handle that surge.
Doing the math you can see that the Generac will run both AC units just fine, at 60% load but will have difficulty starting both of them at the same exact time. (that should generally not be a problem).
I would estimate the life span of any 3600 RPM stand by type generator running those two AC units at no more than 6 months, probably more like 3 months. For occasional camping the Generac will be a good choice, but for ongoing living in an RV you will need a heavy duty unit.
What is a problem for full time use, is virtually any 3500 RPM generator, they tend to have more than their fair share of problems, and were never intended for full time operation in my view...but as stand by short term emergency power generators. The reliable brands run at 1750 or 1800 RPM... those will generally be reliable... cost is two or three times that of these light duty 3500 rpm models.
Onan and a few others make 1750 RPM generators.
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