The Boiler Control 284 is designed to operate up to four boilers to accurately maintain a target water temperature. The 284 operates both condensing and non-condensing boilers that are either modulating, single stage or two stage to provide a flexible, cost effective mixed boiler plant solution with better system performance. The target water temperature is based on outdoor temperature reset or a fixed setpoint for space or process heating applications. Additional loads supplied by the 284 include domestic hot water & fixed setpoint heating. Boiler equal run-time rotation, stand-by primary pump operation & pump exercising all increase boiler plant reliability. The 284 communicates with a Building Automation System (BAS) using BACnet (R) or Modbus (R) for remote monitoring & adjustment capability. tekmarNet (R) Thermostats or a tN4 Gateway 485 can be added to optimize system performance and provide remote monitoring capability.