Looking for A/C advice from 44MY owners

I'm spending the winter updating my new to me 1988 44 Viking MY and would appreciate some A/C advice. My boat currently has what I believe is the original configuration. Here's my current situation:

The boat has two Marine Aire 16K BTU split systems. One of the two condensers in the engine room feeds a single evaporator under the helm. Both the intake and vent are in the salon ceiling (the original arrangement). I don't know the age of this system but the reversing valve sticks and it will only occasionally run in heat mode. When it does run in heat mode it blows 120 degree air, which is good. I bought the boat in November so haven't really be able to truly test cool mode but I assume it blows cold air based on how hot the heat mode air has been during the brief times that the reversing valve has worked. Usually in heat mode the compressor will come on for maybe 20 seconds, then trip an overload, then reset and try again, over and over. If I switch back and forth between AC and heat several times I can sometimes get the heat to run until it reaches the thermostat temp and the compressor kicks off, but then it cycles again when the thermostat calls for heat. Tapping the reversing valve with a screw driver while it's trying to cycle does not seem to help. The tech at the marine tells me it's not really practical to replace a reversing valve on an old unit.

The other 16K condenser feeds two evaporators. One behind an aft stateroom closet and the other behind a forward stateroom closet. This system has 2011 written on the condenser and appears newer. There is a thermostat in the aft stateroom that controls both evaporators. The front stateroom only has an old fan speed dial, no thermostat. The front stateroom fan will not blow at a normal (high) speed. The dial only seems to take it from very low speed to moderately low speed. I think this is a controller problem and not a fan problem. I'm guessing someone replaced some or all of this system in 2011 but did not update the thermostat and controller. This system also has a slow refrigerant leak. It would only blow 75 degree air in heat mode in November. I had the marina tech try to charge it and he was able to get it up to 90 degrees but says it should be at least 110. He said it needs to be charged in cool mode on a hot day to get it any better. The thermostat for this system only goes down to 65 degrees, which is not good for the Chesapeake humidity, at least for me. I like to sleep with the AC at about 60. This insures the compressor will come on during cooler but very humid summer nights.

I have the budget to upgrade these systems. The marina tech thinks I just should replace the stateroom split system with two new self contained units. This could bump up my capacity if I went with 11K or 12K units and would also give each stateroom its own thermostat, and the new thermostats would go down to 55 degrees. The problem is that Marine Aire Units will not quite fit in the old evaporator spaces. I don't think Cruise Air units will fit either. New Marine Aire units are my first choice. The new 230V units are in a sound box and have pressure gauges built in. I would really like these, but they're a little too big to fit in the old evaporator spaces and I can't find any other good location options. The only units with adequate capacity that I've found that will fit are 12K BTU Units sold by a place called the Climate Marine Store in Florida. But I'm not clear on the brand. Modell is CTM-12H which makes me think they are made for this store. I've need to give them a call to get more info.

The salon system has less options. There's not enough space under the helm for a self contained unit and I'm not sure I like the idea of pumping water to the bridge so I'm thinking I'll stick with the split system for the salon. Not really any obvious spots in cabinets or under the dinette for a self contained unit either. I'm thinking of keeping the current system for a season since I suspect it works well in cool mode and maybe some more cycling of the reversing valve will kick it loose. The previous owner stopped using the boat early in the season and never really cycled between modes. I have a lot of other projects going on and if it cools the salon I can live without heat mode in the salon for a season while I focus on getting the stateroom units sorted out.

I'd love to hear what other 1980s 44 MY owners have done and any thoughts or suggestions on how to proceed in getting reliable systems with adequate capacity. Thanks in advance for reading my very long post and and advice you can provide.

Thanks for the input Capt. Ralph. I'll have the tech check the salon system for over charge if I can get him on the boat again boat and I'll listen to see if the reversing valve is clicking when I unwinterize in mid march. Maybe my heat problem is from overcharge. That would be an easy fix. Regarding the front stateroom blower speed, the two evaporators in the two staterooms are identical. I assume they are both 8K BTU evaporators since they are fed by a 16K BTU compressor/condenser. The rear blower is controlled by the thermostat and as you said, the front blower is controlled by a simple dial rheostat mounted in the front stateroom wall. Although they are identical evaporators when the front blower is turned all the way up it spins/blows at half the speed of the rear blower. Both evaporators are very clean. Maybe replacing the rheostatic with a different speed controller might be possible? If I could get the front blower to blow a hard as the rear blower, add some leak sealer to fix the very slow leak (maintenance log says the unit was recharged 7 years ago) get it charged to where it's blowing the spec temps, and can change the thermostat to something that goes below 65 degrees I might postpone the whole A/C project to next winter. I might not have a choice because my biggest issue right is getting a contractor to even come look at it and quote some options.

Also, the copper water lines in the boat are very thick walled. They are definitely not the thin flexible copper tubing sold at Lowes, more like copper pipes. I'm hoping Viking used the same wall thickness for the refrigerant lines, but no way to really tell without cutting a line. It would be quite a job to run new lines, but considering they are 33 years old I think I should take your advice and have them replaced if I go with a new split system, no matter how thick they are.

Did you replace with another split system or did you go with two self contained units?