I am not sure of My BTU, but it is installed under the seat aft of the galley on the starboard side of the boat. The AC vent discharges out from under the bench. I have a problem with it freezing up. There is a grate inside the cabinet under the sink, but I think there is a prblem with the area not getting enough ventilation. If I remove the cushion and the board which exposes the AC unit it will not freeze up. So when sleeping overnight the whole area where two people could sleep needs to be exposed.
Just my experience. I believe if I put another vent in which would open up that area it might solve the problem.