Has anyone tried to make on of these or know where to buy one? I am thinking of converting a fan cooled standard window unit to a water cooled unit for the boat.

I have thought of doing the same thing with a high efficiency 5000 btu unit so that I can run it off my inverter. Mount the fan and evaporator coil under the bed and mount the compressor and water cooled condenser coil and pump in the engine compartment.
Nice and quiet and COOL. Figure that I can do it for about $300 total.

Ya , know...................I've thought along the same lines, EXCEPT ...how about and auto style compressor on the engine and the water cooled condenser. Then , with the evaporator up front , run duct to the dash and guess what you got

Ans. Cool no wake zones

if it's freshwater, you just gotta run a copper tube in a tube and solder it together.

if it's salt, you go with more expensive tubing but the idea is the same.

I still don't understand why you can't plumb an electric AND an engine compressor into a single system and isolate them with check valves. Seems like it would work but all of the marine AC guys I talk to at boat shows say it can't be done.

Beats me why not.

Tinker has the idea. You can buy a new 5k unit from wallyworld for $150 and gut it. Refrigerant lines may get brittle from vibration in an offshore speedster, but then you could always drop the evaporator into a waterbox and make your own chilled water unit.

I'll work on the condenser idea and let you know what I come up with.

If you need a good picture of a tube-style water cooled condenser, check out www.flagshipmarine.com they have some good pix of a simple cupronickel tube in a tube condenser on their units.