A unitary controller is ...

• A. A controller designed for basic zone control using a standard wall-mounted temperature sensor.
• B. A controller designed for central plant optimization.
• C. A network switch.
• D. A device only used for data logging.

Answer: (A)

Unitary controllers handle the control of a single HVAC unit or a single zone and rely on a local temperature input from a standard wall-mounted thermostat. This setup provides basic, self-contained control to maintain the desired temperature in that one area, without coordinating with other zones or systems. That’s exactly what the option describes—simple zone control using a familiar wall sensor. In contrast, central plant optimization involves coordinating many units for overall efficiency, a network switch is just for data communication, and a data-logging device records information without actively controlling the environment.