I travel the nation's interstates when not aboard Escape and I often wonder why the air conditioning systems I see on semi tractors have not made in roads in the marine world. They are inexpensive, efficient, effective, and require no hull penetrations for condenser water. They seem to do just fine in the harsh climate of northern winters where road salt attacks vulnerable metals. What am I missing?
If you are using the heat more than the AC you might want to look at Flagship AC, the unit installed on our boat uses a real heating element, it's not reverse cycle for the heat. We also have a diesel heater like the truckers above that we used when it's below 32, this heats the boat up fast and then the flagship takes over and keeps us warm.
The truck ac is dealing with a LOT less space than a boat unit.
That said, a PO installed a an RV style rooftop unit on my current boat (maybe you cane see it on my avatar). It seems to be doing fine after 12 years or so; although I do occasionally have to treat a bit of rust forming on the exterior grill work. I also pull the cover and squirt some corrosion control on some of the interior metal like the fins.
There is a lot of copper in the quality Dometic DTU marine ac model I installed in the cabin to replace the rotted out original - rot due to long term water in the condensation pan due to clogged drains.
Then you are almost forced to replace with an identical unit. Sort of like take your cousin to her prom
Check out Ocean Breeze. https://www.oceanbreezeac.com/ Made in Stuart, Fl. They used to also make units for Flagship but not sure if they still do or if Flagship is now making their own. Ocean Breeze makes both self contained units and split units and can do custom design as well. Good bunch of people with over 30 years of marine a/c manufacturing experience. No connection, just a satisfied customer. Very pleased with the three units on MOJO.
PO of Pau Hana highly recommended Flagship but at the time we were buying they had a backlog. He had installed their units on the bigger yacht he captained. No experience with Ocean Breeze.
Check out Ocean Breeze. https://www.oceanbreezeac.com/ Made in Stuart, Fl. They used to also make units for Flagship but not sure if they still do or if Flagship is now making their own. Ocean Breeze makes both self contained units and split units and can do custom design as well. Good bunch of people with over 30 years of marine a/c manufacturing experience. No connection, just a satisfied customer. Very pleased with the three units on MOJO.