I am surprised there are so many skeptics when it comes to running AC off of solar. There are many people who already done this in some form already. 3 tons I know specifically is doing it and his setup is very impressive.
With the right setup, 400 to 600 watts of solar and 400AH of battery will get the job done. Now, you might run into issues if you are doing it over multiple days, the solar might struggle to keep up over time but that is when you can bring out the Honda generator and run it for a few hours to top the batteries back up.
In regards to a window AC unit, I think they could be a great option if I was to go the route of trying to combine the furnace and AC into one "box" that goes in the current furnace location. I would probably look for a 7500BTU unit and this is definitely a skilled fabrication job but I'm not seeing any technical reasons it couldn't be done.
Wouldn't a combined AC/Furnance that fits under one dinette seat and vents out the side by much more desirable than having a large bulky unit on the roof?
