I've got a 1986 Catalina 27 and I am considering installing a water cooled marine air condition unit. I would not use a carry on a/c or window unit nearly as much beacuse of the hassle and weight involved in setting it up. Does anyone know the best install location for the unit, duct work and water pump? How about BTU for Florida (I was thinking 9K or 12K becasue of the summer heat). The holding tank is under the V-berth. Wouldn't that location pump that bad smell all over the boat?
Thanks for your help.
I just finished installing a Mermaid 9K unit on my '87 Catalina. I tried my best to figure out how to mount the AC unit up under the V-berth, but I could never work out the ducting issues. There's just not enough free space there.
I ended up installing a shelf inside the port lazarette, right above the batteries, for the unit to sit on. I removed the small access door behind the galley sink and used that opening for the return air. The shelf sits at the same level as the interior countertop, so there's still plenty of room to get to the batteries underneath.
I installed one 4" outlet in the same bulkhead as the return. It blows out over the galley, and since it's located right there at the AC unit, it puts out a good bit of air. (A 6" outlet would be even better, though.) There's another 4" outlet in the starboard quarterberth, with the duct work running across the engine compartment. The last 4" outlet is at the base of the port settee opposite the head. That ductwork runs back through the storage area under the settee, through a bulkhead, then under the stove, then back to the engine compartment where it ties into the other ductwork.
I moved the electric water pump from under the galley sink and installed the through-hull there, along with the 110v AC water pump. The water exits the boat at the stern, alongside the bilge pump and engine exhaust outlets.
I decided on the 9K unit because I'd like to possibly be able to run it off a Honda generator. I'm not sure that you can run a 12K unit off one, but maybe you can. If you can fit a 12K in there, I'd go for it. I can already tell it's going to be running full time when it gets hot.
Hope this info helps.