I installed a 14,000 BTU MarinAire on my boat last year, replacing a 16,000 dometic unit that had died (I think due to poor wiring), I'm satisfied with the brand, I would have gone with a 16,000 BTU unit but I was able to get the slightly smaller unit faster and cheaper. I run it off of the stock Onan 3kw generator that came with the boat, it has no problems at all, mine draws 8-10 amps when running and about 15 at start up, judging by the amp meter on the panel. The 16,000 unit lists 10.8 running and 17.6 at start up, this should be no problem. Everyone loves to hate on that generator but I'm happy with it, it was mounted on insulating mounts and the PO added sound insulation in the engine compartment and below the carpet so it is pretty quiet.
Mine does a good job at the dock with the curtains drawn and a cover across the windshield, it cannot keep up on a hot day with all that glass especially when underway. Blocking the greenhouse effect it very significant. Typically, I'm running from the flybridge while my wife and 3 kids are hiding in the cabin on electric devices (but that is a whole different conversation).
My unit is to starboard, just behind the AC electrical panel and generator controls, I'm pretty sure this is not the standard location. My father had a Mark 3, his was to port, outboard of the fridge and flex ducting was run to a register in the top of the cabinetry at the forward port side of the salon and also a duct running forward to the stateroom. I liked this configuration better than what I have.
[STRIKE]I was pretty sure that AC was standard equipment on all Mark 1's, it may have been removed but you can probably find where the thru-hulls were located and the flex duct was run. I've seen a old brochure listing all of the standard equipment on Mark 1's and AC was listed.[/STRIKE] Edit: I was wrong about this.
