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Join Date: Apr 2006
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Dallas, a small diaphragm pump just won't move much. While "chiller pipes" are a great way to heat or cool any space, the two problems you would have are running enough pipe in your boat to get the heat transfer you want, and then getting enough COLD water through them. To get cold water you typically have to drop an inlet hose below the thermocline, which can be 10-40 feet below surface level. And, if you pump seawater in pipes, critters tend to grow in them and block them, so you need to add a heat exchanger of some type, that you can clean out, and an inlet filter. The heat exchanger means you need two pumps now, one for each side.
Its always "just one more thing".
I've often wondered about using misting nozzles (either for gardening, or the type used on supermarket produce) above deck, letting either fresh water (need a source probably requiring a dock hose) or clean raw water (need good filtering!) mist down on the deck and letting that cool it from evaporation. That's a minimal power system--if you can meet the water requirements.
A white deck, white hull, and canvas (especially covering the foredeck) while not under way would seem to be about the only "sure wins" in bright sunlight.