[C320-list] Marine Air Conditioner

[Charles Holbrook]

Anybody have an idea on the BTU's necessary to keep my 1995 Cat 320 cool.  Right now I have a  9,000 BTU very old unit made by Pioneer located in the aft starboard access above the fuel tank with one vent opening into the aft berthing on port side and one vent into main cabin right above the reefer.  The return air is the whole aft section of boat.  The system does not work very well and keeps cycling off and on with a coil freezing failure alarm.  The coil is not frozen even if the alarm indicates it.  The local Marine AC guy bench tested the unit last year and could not find anything wrong with the unit.  
I'm thinking about just replacing the whole unit and I am thinking about at least a 1600 BTU unit.  Any suggestions out there.     
Charlie, Port Clinton, Ohio "Nautigirl"