Kind of a weird question on a/c for boat

[Bob Sander]

No ice required...... simply use lake water. Use 4" PVC duct to route

That video uses ice
Our river water is nice and cool in May and June but by July when the ac is needed, the water is about room temperature (70'ish).... pretty much useless for air conditioning. Meanwhile we are on a cliff about 35 feet up from the water so when I say "go down to the dock" I'm not kidding.

Here is what you see off our front porch. The red indicates the tips of full sized trees growing off a lower ledge... so at 60 years old now, my enthusiasm for making ice jugs then hauling it all "down to the dock" is not very high! Easier to just flip a switch.




I will say though... the idea of a water cooled ac (as opposed to the normal air cooled) might be worth looking at. More compact, less noise and fewer air ducts. I do have a tank of r134a refrigerant around somewhere. It wouldn't be that hard to convert a window shaker.... build a water cooled evap to replace the air driven evap and mount the whole thing under the sink or something.

 

[dingbat]

Our river water is nice and cool in May and June but by July when the ac is needed, the water is about room temperature (70'ish).... pretty much useless for air conditioning.

I guess its all what you are used to.

We keep the AC set at 75 degrees during the day.....73 degrees at night. Anything less causes the windows and doors to condensate and the wife to complain that she's cold.

Suxs living in the shadow of the Bermuda "Heat Pump" High.

 

[flashback]

You might consider placing the unit on the dock an just duct the cool air to the boat. Keep noise to a minimum.

 

[Bob Sander]

I guess its all what you are used to.

We keep the AC set at 75 degrees during the day.....73 degrees at night. Anything less causes the windows and doors to condensate and the wife to complain that she's cold.

Suxs living in the shadow of the Bermuda "Heat Pump" High.

We run our house at 68 year round, but the point is that you're not going to get much of an "A/C" effect with your 'coolant' (river water) at a temperature of 70 degrees.
One of the big things about cooling Summer air to make things feel more comfortable, is about removing the humidity. Relatively dry air at 80 will feel a heck of a lot cooler than humid air at 80.... and that is part of an air conditioner's function... not just to cool the air, but to remove humidity as well... and in order to do that, the evaporator must be at a temperature lower than the dew point in order to condense the water out. A heat exchanger operating at 70 degrees just isn't going to do that... at least not with any kind of efficiency anyway.