The tekmarNet (R) 4 Setpoint Control 162 is designed to operate a single piece of heating or cooling equipment in order to maintain a setpoint temperature. It can be used in applications, including heating a swimming pool, maintaining a chilled water storage tank, and maintaining a constant slab temperature in a commercial car wash bay. This product regulates a constant water temperature for heating or cooling using one of 6 preset modes (setpoint on/off, hot tub, DHW, setpoint PWM, floor, pool). It has 2 relays (rated at 24 V, 2 A) and uses relay No.1 to control the heating/cooling device, while relay No. 2 can be used for devices such as a DHW re-circulation pump.