Location of powered vent unit

[Night Sailor]

I've always mounted passive and active vents on the centerline of the boat so that they are maximum distance for the water when heeling. In a knockdown under sail it's not likely anyone will think to go close vents, especially in a confined location like a head window.

When solar powered active vents came out I continued that practice for safety and to present a horizontal surface to the sun from any angle when the boat is slipped. I keep the tops clean and usually get two years from the nicad batteries. On my X I find one 4" solar intake vent is enough to keep the boat well found with fresh air when mounted on the horizontal part of the forehatch cover. I have two 4" stainless vents in the main hatch board for exiting air. If you don't have weather covers over the top ends of the main hatch slide rails as I do, then air can exit there, which is the highest part of the interior, where hot air will tend to accumulate. I recommend weather covers to prevent insects and rain from entering from astern when the boat is not being sailed.

[DLT]

I just posted my mod.

[Catigale]

I installed one in the 'Moe' position and one in the front hatch as well.

WHen I experimented with the 'solar angle' I found it happily spun at all angles to the sun - even an oblique angle, and found same on cloudy days too...this at 43N latitude

Mine never stops running until I cover the boat for winter and then I take it and battery out.

I think you need so little power to run these, you dont get the issues you get trying to recharge batteries ...that is my experience FWIW