Yes. I brew beer and use a fridge to brew my beer in as it can be temperature controlled. I use a fridge mate. What this does is it has a heating or cooling mode. So you select the mode you want and plug in the item which you want to use such as a fan or heater. You set a desired temperature say 25 degrees celcius and once it senses the temp is 26, it automatically switches on the fan. By the way im from Australia, this is an Aussie product not sold over the world however im sure there are plenty in America.
I cant post the link becuase i havent made 15 posts yet but if you want to see it go to google and type in ''fridge mate mashmaster'' and the website will come up. Its a small box witha blue front
Cheers
eddy