Originally Posted by brokedown
Presumably the air conditioner is like a car where most of the work is done by an engine driven compressor. The part inside the bus will just be a fan.
That's the way ours is set up. The compressor runs off the engine and the refrigerant was split between the dash air evaporator and the evaporator at the back of the bus.
If you want electric air conditioning you'll need a roof top unit or a mini split.