Room Thermostat II - not working valvetappet (no error message), room too cold

[misa15]

Good afternoon,

Used
- Bosch Home Controller I (10.31.5181-4522),
- Android app 10.31.4176.

Now, for only one Radiator Thermostat II is in Android app showed ventil position (valvetappet) change, but direct on Radiator Thermostat II not hear sound of movement (from 0% to 100%, or back). On other radiators after change temperature up or down is hearable sound of valve movement.
1. Radiator is still cold. Other radiators work like are expected.
2. Direct on Radiator Thermostat II not showed error message.
3. Each Radiator Thermostat II is interconnected with Room Thermostat II. In cold room is the Room Thermostat error or without weak batteries.
4. Batteries on affected Radiator Thermostat II were changed (not showed info about weak battery). Problem is still same.
5. After removing batteries from Radiator Thermostat II, and inserting back was calibrating procedure succesfull (mechanical pin on affected radiator can be moved manually like on other working radiators (all with little bit higher force, no feel difference). Problem is still same (too after reenter batteries).
6. This Radiator Thermostat II was working before (whole last winter (2024) and beginning of this winter (november and december 2025) without problem), only last more days we feel cold in afftected room.
7. All Radiator Thermostats and Room Thermostats had installed last valid firmware version.
8. Created SHC system report 18.1.2026, but no answer from support. And now is in affected bedroom 15,2 oC.

Thank you in advance for smart help.

P.S. During december were one Radiator Thermostat II exchanged (in the different room), but there was showed error E03 or E05 (I am yet not sure).

[misa15]

Sorry inserted in wrong sub forum...

[Tidy]

In the App under devices you can see the valve position indicated in 0% - 100%. Does that value change, when you change the setpoint temperature?

[misa15]

On affected Room Thermostat II

1. Changed requested the temperature on higher like it is (e.g. it is 16 oC, requested 25 oC). On device flash while red light. In app showed 100%. No hear sound in device.

2. Changed requested the temperature on lower like it is (e.g. it is 16 oC, requested 10 oC). On device flash while blue light. In app showed 0%. No hear sound in device.

In other devices, after change requested temperature hear the sound of change valvetappet.

P.S. Meanwhile found same topic from other user on this forum for same issue...  

[Tidy]

Sounds like a problem with the device, I think you should contact the support.

[misa15]

Support contacted, yet asked for check error in app (not exists) or try to change devices... Will see real progress and solution later.