Desigo RXB is an innovative range of controllers and room units. Data communication is based on KNX/EIB technology.

Desigo RXB hardware

The range comprises compact controllers, easy-to-operate room units and controllers in room-style housings. The input and output configurations of the controllers, and the housing style are fully optimized to suit their field of application. The HVAC functions are operated with standard room units or controllers in a room-style housing.

Desigo RXB software

Each controller is loaded with a selection of application software which contains the control program for the associated room or area within a room.

The ETS commissioning and service tool is used for the engineering and commissioning of a network incorporating the Desigo RXB range. This tool also supports the creation of communication bindings between KNX/EIB-compatible devices (Desigo RXB or third-party devices).

Example: Fan coil system








Two-pipe system with changeover

Four-pipe system

Four-pipe system with room supply air cascade control

Four-pipe system with damper control

RXB21.1/FC-10 (in phase-out)

RXB39.1/FC-13 (in phase-out)



Two-pipe system with changeover and electric reheater

Four-pipe system with electric reheater

RXB22.1/FC-12 (in phase-out)

RXB39.1/FC-13 (in phase-out)




Two-pipe system with changeover and outside air

Four-pipe system with outside air

Two-pipe system with changeover and radiator

RXB21.1/FC-11 (in phase-out)

Common functions:

  • Window contact, occupancy sensor, four operating modes
  • Manual fan control with room unit
  • Automatic fan control (three speeds)
  • Options with two-pipe systems: Heating only, cooling or changeover via KNX/EIB bus