I'm researching a secondary AC system for AMBOT to supplement the 24,000 BTU Hoseline unit model 1131. I've considered retrofitting the existing system to run off 115V, but according to Hoseline its pretty much replacement of everything and the replacement is another giant AC system meant really only to run off shore power. Trying to do something custom is still trying to support a system with a BTU not designed for any off-grid provisions. So I'm going to leave the existing system alone and use in emergency or while the vehicle is running for both heating and cooling.
I've considered a window unit but one of my goals is to keep the compartments usable as much as possible for storage. I've also looked at all the 3000-5000 btu systems out there and are all interesting, but what they all lack is the inverter compressors that are found in the mini split systems. Having a variable range 3,070 ~ 12,120 BTU allows you to not only adjust for cooling based on current temperature but also on available energy. If you are off grid at night with only your batteries, put the thing on quiet mode and a sleep timer and let it go for a few hours and turn off.
This is the unit i'm looking at
http://www.ajmadison.com/cgi-bin/ajmadison/M09CJ.html
At 680 watts, 6 amps, or about 60 DC amps, which my batteries will do 3 hours till 50% if the compressor was always on. That would get me thru the night just fine.
During the day, a honda EU2000i or Yamaha will provide the AC power if needed. The variable speed inverter compressor paired with a variable speed inverter generator will allow both units to increase or decrease supply and demand automatically.
My solar is good for 480W max so I could not run the unit directly off solar. A generator is a must. I plan to have the dual setup for 30A. One would run to supplement the AC and the other only as needed for multiple high current needs or battery recharge.
The dual alternators can provide up to 270 amps.
The condenser will be mounted above the rear bumper along with the spare tire. They will be mounted to hinges to allow access to the rear entry as needed. It will also serve to extend the condenser 90* so there is free air flow and the unit is positioned out of the way. The air handler is going above the rear doors, attached to the roof extension.
Well that's how it all is today, I need to make a decision and get on with it. My concerns are how well it will hold up to being mounted on a truck, so I'm going with a quality brand and we shall see how it goes. I just can't find a more efficient unit that will easily cool the box when AC or generator is going, yet still maintain some temperature control when needed on battery alone.
Soon I think AC on solar and battery will be feasible with new technologies like the Tesla Powerwall provided you have a means to recharge it daily.
its very inefficient compared to a decent split system. Our 6800BTU split system uses less power than that unit yet has more than twice the output. 
