What kind of vents did you end up going with? I've seen coop with Ac's!!!
Just some Duraflo roof vents, I put in two because I need the light as well as the ventilation.
So I tested keeping the shed door shut tonight, and all of the chickens but one went in - but half of them were roosting on the floor. For some reason, they do not like to go in to the darker coop. I have a window I'll put in tomorrow too, and see if that helps. If all else fails, I'll put in a small night light for while we are gone, since I really need them to be inside the coop and not locked out by the new automatic door!