Fan coil unit (FCU) uses a fan and a coil/s to heat or cool a room. Air fed to the FCU can be from the AHU’s duct work (when used with chillers) or directly from the room (without duct work).
The FCU is usually found in HVAC systems of residential, commercial, and industrial buildings. FCU can either be horizontal (ceiling mounted) or vertical (wall mounted).
FCU controls would include a controller and a room sensor/ thermostat for zone air temperature control.
The main goal of the controller is to keep the zone temperature within the user-defined setpoints by driving valves, allowing hot or cold water to flow through heat exchanger coils as required, and then circulating air past these coils into the zone via a fan.
See below sample example of a FCU Prolon controller.
Prolon C1050 Fan Coil controller
Since the default communication for the most of these controllers is Modbus or BACnet, see
here how to interconnect them wirelessly to a network controller for building management system integration or to other controllers with wireless Modbus or wireless BACnet device.
Compatible Prolon digital communicating sensors that can provide the C1050 with room temperature, room setpoint, and schedule override include T1000, T500, and T200.
Fan coil systems can either be 2 pipe or 4 pipe systems: