two things to be concerned about on a fast boat.

1) genset water pickup.
2) A/C water pickup.

Scoop pickups are best, but can cost a little speed.
Mushroom pickups are worst, but can be made to work okay.
Transom mount pickups are the best. Can be adjusted to provide the best of all worlds.

A scoop P/U is O.K. for an A/C unit but not for a gen set. A friend of mine found this out the hard way. When under way the scoop forced water past the genset raw water impeller and this in turn forced water through the block into the exhaust riser. If the gen is not running it will flow back into the engine causing hydraulic lock the next time you try to start it. This might not be an issue if your exhaust system flows down hill from the riser to the outlet, but most installs that I have seen it flows up then down.

Steve Hixson

Yes, it will work just like the heat pump in your house.

Has anyone heard about the Bay Air A/C? THis is the unit that runs off of the cooler water. It is a 6500 BTU A/C. I just wonder if it works as claimed!

Troutdozer,

Reverse cycle heat is EXACTLY like a home heat pump. In cool weather (and cool water conditions) it will heat your boat with supply duct air temps approx 20 degrees warmer than the return air temps. If you get to the boat and the cabin temp is 45 degrees, then for the first 20 minutes, your supply air temp will be about 65 degrees, then the next 30 mins, it will be 85 degrees. Probably will take 45 mins for the cabin to reach the temp you desire.

If the water temp is COLD, then the unit will be far less efficient. Probably a ten degree differential. And once the water temp goes below 40 degrees, the reverse cycle will probably stop working altogether (no discernable heat from the unit).

The only reason I mention this is because you live in an area that can get damn cold. Reverse cycle is great for boating in cool weather, but not cold weather.

Resistance heat (either installed ON the unit, or by means of a $14 WalMart space heater) provides instant reliable heat in the coldest of weather...

Reverse cycle adds about $100 to the cost of a unit. Well worth it as long as you know its limitations. A space heater is your best bargain for use when it is truly cold out.

You got it.
Overnight usage, reverse cycle heat is actually the most comfortable heat you can have. Encourages even temps throughout the cabin, because it adjusts temps gradually. For quick heat, the cheap space heater is the best bet.

Gotta keep those wives warm. Otherwise their monks will freeze up. And a stabbin cabin is no place for a petrified monk.

cheers.
mc

Sir,

The company in Tampa you mentioned was Anchor Manufacturing, they are out of business sadly! I was the designer of the Marine Comfort Products for them and the Engineer.

Mike

Yes it is true but how do you keep the pick up down that deep in a running current or if the waters not that deep your out of luck! As for 6,500 Btu's I would love to see the math on that calculation

I have had customers trying to do this with batteries and It doesn't work also 5,000 Btu's is not much AC.
Cabin Length x width x height x 11 is fairly accurate in calculating heat load

We have a unit that might fit your needs, one is 4000 btu and one is 6000 btu.http://www.coldmarineair.com