Tekmar Boiler Control (9 Stage Boiler & Setpoint). Boiler Control 268 is designed to stage multiple boilers using Outdoor Temperature Reset. It can be used in applications ranging from baseboard or mixed radiant heating systems, to dedicated domestic hot water heating in commercial buildings. This control regulates a single heating water temperature through Outdoor Temperature Reset and/or Setpoint/DHW target control. It is capable of controlling (stage and rotate) up to 9 on/off boilers as well as system pump.