The Model HE-CNTRL air sensing thermostat is a replacement for the original "bulb and bellows" thermostat, used to protect from freezing your Hawkeye Steel livestock waterer. Unlike the original concept of the submerged bulb to sense water temperature, this unit senses the air temperature immediately surrounding the water basin, therefore, it is not designed for water submersion. DO NOT SUMBERGE THE REPLACEMENT SENSOR, it is only designed to sense the temperature of the air. It will turn on the heating element at 45 degrees Fahrenheit and off at 60 degrees to provide reliable freeze protection with the waterers. It is not adjustable for temperature.
