Tekmar tN2 H. Cntrl -Boil, SP, DHW, MXG,4 Z-pumps. tekmarNet??2 House Control 403 is designed to operate all of mechanical equipment in a residential hydronic heating system, coordinating ir operation through network communication. It can be used in applications ranging from a single zone of baseboard with an on/off boiler, to multiple fan coils, mixed radiant floor heating zones, and a modulating/condensing boiler. This control regulates up to two heating water temperatures through Outdoor Temperature Reset and Indoor Temperature Feedback. It is capable of controlling a single on/off, two stage, or modulating boiler, a mixing device, Domestic Hot Water, setpoint loads, 4 on-board zone pumps, and can expand up to 24 zones in total for each space heating water temperature.