Re: No A/C when motoring?
The comparison of a car to a boat is not a good one, for several reasons:
As Denise noted, your typical auxiliary engine in a sailboat is way smaller than the one found in your average minivan -- think about 1/4 or less of the output.
Compounding the issue is that the volume to be cooled inside a boat is probably at least double of that in the minivan.
Certainy not an insurmountable problem, but really expensive to solve.
If you want to run an engine driven system, then you've got to drop in a new larger one that probably won't fit in the space designed for it by the designer. This could also throw off your wieght/balance and cause trim issues. You also would almost never get the engine anywhere near its optimum power curve, unless you're running the a/c constantly. This is not a great thing for a diesel engine.
The more typical solution is to install a genset that can handle the load needed to run the a/c. Only runs when you need it, can also be used on the hook, etc, etc. However, they don't come cheap, and also pose a challenge trying to carve out space for it as well as the weight issues noted above.
Most people find that 12v fans are a good enough alternative.
Last edited by PorFin; 07-12-2012 at 10:08 AM.