which one? none of these types of solar venters are primarily designed for cooling... in hot weather, you make sure they are switched off! if they have a cooling mode, then likely it's a secondary feature, and in the case of mine, pumps cool air from outside the house, in at night, when the outside temp drops.
it should be noted though, that as long as there's any wind - opening a couple of windows does a much better job :) |