Boat A/C Anyone

[MarshMan73]

Does anyone here know something about boat A/C's? This one is on a 56 foot sailboat. It has no ID labels left on it anymore. Unit runs, but doesn't cool very well. Seems to have either weak glycol solution or incorrect charge. Unit is a 115V, R-22 based, cap tube system. Utiilizes seawater for condenser section and glycol solution for running 4 evaporators. It also has a reversing valve. It is in essence a water cooled reverse cycle chiller. Pressures are running 200/60psi. I am a seasoned refrigeration and A/C technician, but have never worked on such a system. Does anyone know the correct superheat or subcooling values to expect from this thing or how to ID it so I can get in touch with a manufacturer?