Holly bought me 2 Bayliss auto openers when we assembled our GH. I did have to add a 2" piece of aluminum angle to make them mount better. Otherwise they seem to function well, possibly too well. Sun light seems to warm the cylinders too easily, and on sunny fall mornings they open before the ambient temperature requires it. They do operate well and increasing the weight may help, as well as wrapping the cylinders with aluminum foil. I plan to write them about this.
As too the vents closing tightly, the problem is with the vents themselves, as Dave mentioned. They are so flimsy, they wobble. Bending slightly helps to tweak them but next spring I want to try and make them more stable. I'm thinking adding a crisscross of 1/4x1/2" aircraft aluminum from corner to corner may solve this problem, especially since the hinge piece in it's self seems sound enough.
The Bayliss product is a quality one. Prices vary a good bit between suppliers so shop around.
http://www.baylissautovents.co...
