Quote Originally Posted by chaz7979 View Post
I was thinking maybe there was something like a vent that manually closes or works at a certain temperature but, I'm guessing by the responses that these things must not exist.
Powered fans with a thermostat are actually common. I think self closing vents louvres can be had to accompany them. Just search powered attic fan an you will find those with a thermostat mixed in the results.