Homematic SET_TEMPERATURE command is not processed / not sent

I set up openhabian a few weeks ago and I am still struggling with sending temperature commands to the HG-HM-CC-RT-DN thermostatic rc radiator valve. I did not find any issue in the forum so far.

My configuration:

  • Raspberry Pi2

  • busware CUL V 3.1

  • openhabian 2.5.10

  • openHAB2

  • Homematic Bridge


  • AVM FRITZ! Binding


  • Homematic HG-HM-CC-RT-DN thermostatic rc radiator valve

I used the UI for the configuration. Unfortunately I did not find the “code tab”, so I cannot add this information to explain the problem. The bindings and items seem to be connected. I get the right status information (e.g. about the temperature, valve setting etc.). So I can recieve data using the connection.

The aim of the configuration is to set the temperature at the Homematic HG-HM-CC-RT-DN thermostatic rc radiator valve to a defined value (e.g. 17,00 °) at a specific time. The defined rule itself seems to work. A new value is processed but does not reach the rc valve. If started manually I get the inforamtion “Rule executed.”

The set temperature is just not recieved by the HG-HM-CC-RT-DN thermostatic rc radiator valve. Instead the log shows the following information: 2021-01-09 21:43:32.139 [WARN ] [ule.handler.ItemCommandActionHandler] - Command ‘17,00’ is not valid for item ‘homematic_HG_HM_CC_RT_DN_b86ea60f_LEQ0848606_4_SET_TEMPERATURE’.

When trying to set the temperature using the UI I get a “ERROR 400: Bad Request” response. The corresponding information in the log file is: 2021-01-09 19:17:02.308 [WARN ] [rest.core.internal.item.ItemResource] - Received HTTP POST request at ‘items/homematic_HG_HM_CC_RT_DN_b86ea60f_LEQ0848606_4_SET_TEMPERATURE’ with an invalid status value ‘17 ?C’.

I appriciate any hint and ideas fixing this issue. Thanks


The temperature channel is defined as Number:Temperature, that is you must use the correct unit when setting value.

You can find more information here: Rules | openHAB

Thanks MHerbst,
unfortunately I am still lost with this issue. I just can not figure out what would be the correct Input to the action description in the rule Setting.Unbenannt_1

I did all configuration with the paper UI and I recieve all the status data from the thermostat. Do I need to do anything else? Or configure other files?