The real question is where are you at and what is the average daytime temperature. I assume you are using a heat exchanger A/C unit and not refrigerant. The heat exchanger only reduces the air temperature to the ambient water temperature meaning if the water is 80 degrees and the outside air is 80 degrees you will not obtain much cooling. Therefore, the cooler the water temperature the less BTU required. The diffcult part of the A/C install is finding room to install it. 12,000 BTU should be sufficient to cool a 30 foot Catalina.
Fred, My 30 Catalina has a 10,000 BTU unit and it does a great job. It is located in North Carolina, we get into the mid and upper 90s often here. I think you will do fine with a 12,000 BTU unit. Chip
had a catalina 30 footer....16,000 was just barely enough when we had 110 degree days for a couple of weeks in '96. i would put the most you can afford....the labor is the main expense. the more powerful unit will not have to work as hard. i now have a 380 i did the air and put 28,000 in 2 independent units.
I installed a Mermaid 16,500 reverse cycle to my C30 two years ago, and have had plenty of cooling. It takes about 30 min to go from 100+ to the mid 70's. We put the compressor in the aft part of the cockpit lazarette and have had no problems with the installation or the quality of the Mermaid product. You can buy the unit cheaper from Defender than you can from Mermaid direct. We also put a Y valve on the thru hull for the macerator, and use this as the seawater intake to avoid putting another hole in the hull. If you decide to use the macerator thru hull, be sure to isolate the macerator switch. (mine is relocated to the engine compartment.) The installation is fairly easy if you are at all handy. I have been pleased with the performance.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
