When it is hot enough to warrant air conditioner use, it may be cheaper and better to find an inexpensive campground or other shore power connection.
Here is a site to help find inexpensive and sometimes free places to stay:
http://freecampsites.net/I've added a remote control for the electric start on my Yamaha 3000 sIEB. It is so nice to be able to start and stop it from inside the RV.
Here is why I believe you may need a "bit more power".
In the mountains, the Yamaha 3000 by itself can sometimes overload when attempting to start my 13500 btu roof air conditioner. I mated it to a 3000 watt Magnum hybrid inverter, and that solved the occasional over load at high altitudes. I was in Cranbrook, BC both before and after the new Magnum. The altitude at that location is 3,021 feet. Derating for the Yamaha is about 2 to 3% per 1000 feet.
A 15000 btu air conditioner is going to be just that little bit harder to start than a 13500. Without the Magnum hybrid inverter I really doubt that there will be satisfactory results using the Yamaha 3000 iSEB.
