T&T: "the best" AC system?

[Cole on Voyager]

This past winter was my first on my new boat which is equipped with two Cruiseair 16K BTU reverse cycle units. I monitored the water temperature all winter. The units would make heat as low as 38 degree water temp, but they were probably working very hard, the forward unit also froze the water one time. I didn't use them below 45 degrees after that freeze up, as I consider myself very lucky I didn't break something when that happened. My units have one pump for both and thus do not get as much flow as I'd like to see. I am on the hard now and one my projects is a second intake so that I can plumb them to individual pumps. I feel with good water flow to prevent freezing up 40 degree water temp will be my break point.

Cole




Can you enlighten us to the break point sea water temperatures for efficient
use of the heating side of the heat pump systems?  I was under the
impression the Puget Snd mid-40 deg.