The Heatcraft Refrigeration 5521R 2-Wire Thermostat is a temperature control component designed for commercial refrigeration systems. It operates within a 40°F–50°F temperature range, automatically responding to temperature changes to regulate fan operation and maintain consistent cooling conditions. Commonly used in Heatcraft refrigeration units, including evaporator and condenser sy... https://www.partshnc.com/5521r-heatcraft-refrigeration-2-wire-thermostat