If i have a vent in the floor of the bus under the coolbox, and have a fan to direct air so that it is expelled through the floor via the gas exhaust outlet on the fridge, that would be sufficient for standstill use wouldnt it. I am thinking that the fan to direct the flow of air through the floor would draw ultra low amps and therefore we could use the gas and save on battery usage. this is the idea, subject to the gas exhaust being in a suitable place. The bit to the right is front seat and wheel arch etc. (i deleted CAD from my computer like a knob the other day, hence MS Paint)
this is what it says in the manual Area of use The cooling unit must not be installed in motor vehicles and boats when using the gas operation method! Operation using liquid gas in enclosed spaces in not permitted! THIS COOLING UNIT MAY ONLY BE USED WITH GAS OUT OF DOORS! Outdoor use includes tents (awnings) which are well ventilated throughout unit operation and flat garden terraces. There are no restrictions on electrical operation. Site of operation must be protected from rain and other water sources.