Room unit RCD20

Room unit RCD20



    Digital room unit RCD20 is used to control the room temperature in connection with the SELTRON heating controllers.

    • In domestic buildings for setting and monitoring of the requested room temperature in connection with SELTRON controllers WDC, WXD, KXD and AHD.


    • Easy and comfortable setting with the use of a smart device (phone).
    • User functions PARTY, ECO, HOLIDAYS, FIREPLACE and one-time activation of DHW.
    • Measurement of relative humidity in the room (option)
    • Measurement of the air quality in the room (option).



    Featured functions

    Selection of the operation mode

    On the RCD20 room unit, you can easily and quickly select or change the operation mode shown by the icons at the bottom of the screen.

    Room thermostat Seltron powered by a rechargeable battery

    The wireless model of the RCD20 room unit is powered by a rechargeable battery. Discharged battery can be charged with any charger that has USB-C connector. This saves on the cost of annual battery replacement and avoids potential damage to the unit in case of battery spill. The connection for charging the battery is located on the bottom part of the housing.

    User functions

    The RCD20 room unit has PARTY, ECO, HOLIDAY, FIREPLACE and DHW user functions, which allow the user to adjust the operation of the control to their preferences at any time.

    Technical data

    Tehnični podatkiRCD20
    Wall installation or onto a flush socket
    CommunicationModbus, wired connection
    Power supply12 V DC, bus line
    Own consumption< 0,02 W
    Accuracy of built-in clock+/-1 s (24 h) at 20 °C
    Degree of protectionIP20 according to EN 60529
    Safety classIII according to SIST EN 60730-1
    Type of temperature sensorsRTD Murata NTC (10 kE)
    Housing materialPC+ABS – thermoplastic
    Permissible ambient temperature0÷40 °C
    Storage temperature-20÷65 °C
    Product weight115 g
    Number of pieces in a package unit24 pieces
    DimensionsRoom unit RCD20 and RCD40 dimensions
    Electrical connectionRoom unit RCD20-W RCD40-W electrical connection

    Performance comparison

    Technical features
    Max. number of room units on heating controller WXD, WDC, KXD, KUD, KPD22
    Max. number of room units on zone controller ZCE66
    Max. number of room units on compact weather compensated controller CMP, AHC, AHD11
    Wired connection with controller
    Wireless connection with controller
    Option of connecting an auxiliary senso
    User functions
    PARTY function – activation of the comfort operation mode
    ECO function – activation of the economy operation mode
    HOLIDAY function – activation of the operation mode during the holiday season
    FIREPLACE function – activation of operation with parallel heating (with FIREPLACE)
    DHW function – one-time DHW heating
    Data display
    Display of actual measured and set temperature
    Display of temperatures, measures on controller
    Display of battery status and need for recharge
    Display of outdoor temperature
    Display of screed temperature
    Setup and installation
    Wall installation


    Dear customers!

    Please be informed that our store Seltron d.o.o. will be closed on the following days 12-13 January 2024 for annual inventory purposes.

    Thank you for your understanding.


    The Seltron service will be closed from 27 December to 29 December 2023.

    Any emergencies or issues that arise during our absence will be dealt with as soon as the service reopens on 3 January 2024.

    Thank you for your understanding.