[aerohead]

Originally Posted by Ecobalt

I installed a mini-split system two years ago. Don't be afraid to tighten those pipe fittings! I tried to follow the "torque spec" in the manual and put them on too loose. I had to pay to have the system recharged. It did not need to be evacuated, though.

Use two real wrenches, not adjustable wrenches, and tighten them enough that the nut grabs the tubing and starts to twist the tubing with it.
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I am still not sold on the roof top AC. Perhaps an aeromodder could build a teardrop shaped fairing that tapers back for a long distance.

It occurred to me that a minisplit AC may not have the vibration rating that a real RV AC needs. If you go that way, I would recommend shock absorbers on the axles.

orbywan has fabricated a streamlining fairing for his A/C unit.You might want to check out his RV build thread.