The tekmarNet (R) thermostat 552 is a communicating touchscreen thermostat designed for hydronic heating systems. The extra large touchscreen display allows you to easily adjust 7-day programmable schedules and room temperatures to optimize comfort and energy savings. It operates a single zone of heating and has two auxiliary sensor inputs that can be assigned to measure room, floor, or outdoor temperature. An optional floor sensor allows precise heating of radiant floors by controlling the floor temperature and maintaining the desired room air temperature. Alternatively the room air temperature sensor can also be disabled to solely maintain a minimum floor temperature. The 552 can be wired using 2 or 4 wires to connect to tekmarNet (R) zoning controls, or can be installed as a stand-alone thermostat using 3 wires.