The Franklin Maverick Thermostat regulates the heaters in the following Franklin automatic waterers:
INSTRUCTIONS
Preset Thermostat (blue disc on side of trough - outside of trough). Skide thermostat to the right to turn it up and slide it to the left to turn it down.
OR
Plate curves under trough and may be moved closer to trough to shut off. Pull away from trough so cold air can hit thermostat and turn it on.
***Warmer - pull down / Cooler - push up***
Turns Franklin Heaters on at 36 degrees and turns off at 48 degrees.