Looking for solar panel controller

[spartannation]

I have a warm air solar panel that I want to mount on the south side of my garage to cut down on heating costs. The panel I have has an 8" duct on each end and my plan is to cut two holes through the wall, mount the panel and connect a temperature controlled fan to move the air through the panel. The problem I have is that I can't find the controller I want and thought maybe someone out there can point me in the right direction. What I'm looking for is a sensor to put inside the panel connected to a controller that connects to the fan. What I want it to do is turn the fan on when the panel temp reaches, lets say, 85, then turn the fan off when the temp drops to 75. I'm throwing these numbers out as examples. I'll wire in a switch for turning the fan off during warm weather. I've done numerous google searches with no luck. Can anyone help? Thanks in advance.

[Barnacle Bill]

How about power roof vents? I use to have a couple that kicked on/off according to temp.

[CatFan]

NC Adjustable Temperature Control Switch Thermostat 30-110 Degree Celsius | eBay