Going by the various reports on here if I was buying one mainly to run the AC I would go a 2.4 at least, a 2kw may or may not run the AC even the same model AC some will, some won't.............With my old set up I would run up my Honda 2kva for a few minutes then switch on the AC at a mid way setting and gradually increase if needed, the genny wasn't going flat chat but you knew when the AC cycled but you wouldn't run anything else off it while AC was using it, yet same model AC on another rig it wouldn't run it, genny would stall.........