Seems to me I had this replaced maybe 20 years ago and now it’s failing to close completely again. Surely somebody out there has come up with a workaround. There are so many inexpensive electronic temp sensors, timers, solenoid air valves, etc available on eBay, that there must have been someone out there clever enough to have engineered something more elegant than a cable-operated butterfly. Before I embark on that journey myself, I’m hoping that clever someone might share their solution.