The Universal Reset Module 423 is designed to operate all of the mechanical equipment in a hydronic heating system, except for zones, coordinating their operation through network communication. It can be used in applications ranging from a single zone of baseboard with an on/off boiler, to four temperature systems comprised of multiple fan coils, baseboard, mixed radiant floor zones, and two modulating/condensing boilers. This control regulates up to four space heating water temperatures through Outdoor Temperature Reset and Indoor Temperature Feedback. It is capable of controlling two on/off or modulating boilers, Domestic Hot Water, set point loads, and can expand up to 24 zones for each space heating water temperature (96 in total).