Therm Products - Hot Spring Hi Limit Thermistor Assembly

High-Limit Thermistors are a safety device for spas and hot tubs designed to automatically turn off the heater if the temperature of the water leaving the heater exceeds 118 degrees Fahrenheit. They are installed by screwing one end into the No-Fault heater housing and plugging the other end into the side of the spa's control box.

See Owner's Manual for details