CO2 sensor with humidity and room temperature controller for KNX
System 55

Order no.
Packing unit
cream white glossy
Order no. 2104 01
2104 01
EAN 4010337084464
Packing unit 1
PS 06
pure white glossy
Order no. 2104 03
2104 03
EAN 4010337084471
Packing unit 1
PS 06
pure white matt
Order no. 2104 27
2104 27
EAN 4010337084495
Packing unit 1
PS 06
Order no. 2104 28
2104 28
EAN 4010337084501
Packing unit 1
PS 06
colour aluminium
Order no. 2104 26
2104 26
EAN 4010337084488
Packing unit 1
PS 06
black matt
Order no. 2104 005
2104 005
EAN 4010337037231
Packing unit 1
PS 06
grey matt
Order no. 2104 015
2104 015
EAN 4010337083047
Packing unit 1
PS 06
stainless steel
Order no. 2104 600
2104 600
EAN 4010337021506
Packing unit 1
PS 06
Recommended retail price. Price system (PS) not equal to 1, 14 = reduced discount.
Discontinued item. Available until 12/2024.
CO₂-sensor with an integrated KNX bus coupler and two binary inputs for measuring the concentration of carbon dioxide, relative humidity, and room temperature.



  • Limit value monitoring for CO2 concentration and humidity.
  • Dewpoint alert for cooling ceilings and conservatories, for example, to prevent potential mould growth.
  • Two binary inputs for connecting zero-voltage contacts.
  • Logic gates for simple linking functions.


  • Up to four different limits can be set for the CO2-sensor.
  • Adaptation to current sea level above NN.
  • Max. two limit values can be set for the humidity sensor.


  • 5 operating modes: Comfort, standby, night, frost or heat protection, and controller lock-out (e. g. dew-point mode).
  • Heating/cooling functions: Heating, cooling, heating and cooling, basic and additional heating, basic and additional cooling.
  • Preset control parameters for common radiators/cooling units.
  • Controller can be deactivated (dewpoint operation) or controller or operation of the controller can be blocked.
  • Valve protection function (valve is opened cyclically every 24 hours).
  • Control types: continuous PI control, switching PI control (PWM), and switching 2-point control (on/off).


  • Free assignment of the functions switching, dimming, blind and value transmitter to the inputs.
  • Blocker for blocking individual inputs.
  • Behaviour can be configured following bus voltage recovery.
  • Telegram rate limiting.
  • Switching function: two independent switching objects are available for each existing input and can be enabled individually, command for leading and trailing edge can be set independently (ON, OFF, CHANGE, no reaction).
  • Dimming function: Single-surface and double-surface operation, time between dimming and switching and dimming increment can be set, telegram repetition, and stop telegram transmission possible.
  • Blind function: command can be set with rising edge (no function, UP, DOWN, SW), operating concept can be parameterised, time between short and long-term operation adjustable, slat adjustment time adjustable.
  • Encoder and light scene auxiliary unit function: edge (push button as NO contact, push button as NC contact, switch) and value with edge can be configured, value adjustment by pressing and holding a button for value transmitters possible, light scene auxiliary unit with/without memory function.

Technical data

KNX medium:

Measurement range
CO2 concentration:
0 to 2,000 ppm
10 to 95% rel. humidity

Cable length, inputs:
Max. 5 m

Protection class:

Connection cross section
2.5 mm²

Installation depth:
23 mm

Ambient temperature:
0 °C to +45 °C


  • The CO2-sensor does not have any operating or display elements.
  • The use of a switch terminal box for connection of the external inputs is recommended.
  • A separate bus coupler is not required to operate the CO2-sensor.

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CO2-Sensor with humidity and room temperature controller
Operating instructions

Operating instructions.

Order no. 2104 ..

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CO2-Sensor with humidity and room temperature controller
Technical Documentation

Technical documentation.

Order no. 2104 ..

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CO2-Sensor with humidity and room temperature controller
Product database

Product database from ETS3.0d, 5.654 KByte.

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