And being that this RV would be for travels in Australia we really needed to get some air-conditioning in.
H had dedicated, early in the project, the whole roof area to solar panels so we couldn't install a system on the roof, nor did we want to. Aside from that being a space compromise, it would be exposed, add wind resistance, would possibly shade the solar panels and possibly get knocked under a tree. What we wanted was a system to work from within the engine compartment. And at first this proved very difficult.
The local air-conditioning business simply told us it was too difficult, they couldn't do it, it'd be too expensive, and honestly they didn't seem to want to think about it. We walked away from there still determined to do it but wondering where we'd get help from.
We looked at truck sleeper cabs systems and had some good advice there that the 'ice-pack' system wasn't right for us but they nudged us in the right direction.
Slowly we were starting to piece together a solution. Then I went out for coffee with an old friend. She casually said 'hey, you know my husband is doing air-conditioning now?' He's primarily a farmer so I hadn't known. It was soon arranged that he'd come for a look at our project. We were in luck because he's a man that happily takes on odd projects. He (N) doesn't promote his work because he still farms and gets enough work to keep going with.
The biggest challenge was to find space on the engine to install the compressor, but H & N did. And then we had to get pulleys made to take the drive power from the engine to the compressor of the air conditioner. After that it was a simple installation of the evaporator, hoses and wiring.
Our installed air-conditioner is an after-market under dash mount style (although we installed it at the inner ceiling). The biggest we could have is for a vehicle no larger than a van so it's very useful that we have a dividing door in the bus to separate the bedroom off. Thereby, we only aircondition the front part of our home.
Our air-conditioner only works when we are driving (have the engine running). Additional to this we have a 12 volt ceiling mounted RV/yacht fan in the bedroom, and, because we've got so much power from the solar and those 12v fans are so expensive we also have a cheap 240v box fan that we use in the main living area. We mostly put it onto of the fridge, held but movable with good magnets.