Z-Wave network/nodes not reachable - weird behavior

Hi Everyone!

I’m fairly new to tinkering with Z-Wave devices, but I have a rather complex with it.
I bought my Z-Wave devices about a year ago. Eurotronic Spirit TRVs (battery) and a Heltun Floor Thermostat (mains). The controller is an Aeotec stick.

Information:
openHAB 3.3.0
Raspberry Pi 4 4Gb

When I installed it, everything worked. I used it throughout the winter with (almost) no problems.
Obviously we did not used these in the summer, but I did nothing with them, let them run through summer (at least I get temp readings).

Right now, most of the nodes don’t work.

  • The Heltun thermostat (mains powered) sends temperature and other readings, but seems that I can’t send any commands to it. I can change the temperature in openHAB, shows as its changed (the setpoint changes) but in reality it does not change. The log is full of the readings from this node. Sometimes after I try sending some commands to it, it goes into OFFLINE state
  • Most of the thermostats are not reachable. Some reports OFFLINE state, some reports ONLINE state. When I try to change the setpoint, it usually does not work, and it does not even change the Setpoint value
  • Sometimes the controller seems as it is stuck. If I soft reset it, sometimes it won’t come back online, and it changes the device descriptor from /dev/ttyACM0 to /dev/ttyACM1 and back to ACM0 if I reset it again later. I have read somewhere that Raspberry can’t handle that stick and you need to use an USB Hub. This is still the case, should I try an USB stick?
  • I have replaced the batteries in one of the TRVs some week ago. It never returned to ONLINE state after that. It did not reset itself completely because the Node ID is correct, I checked it.
  • Network heal is enabled (2AM) but all of the devices report 2-3 months old last heal time.

I don’t know where I should start troubleshooting this, some advice would be great!

Thanks for the help in advance.

Absolutely go for a powered USB HUB for the stick. Should do the trick.
This also applies to Zigbee sticks should you ever expand.

Thanks! Any other advice? Some nodes seem to work properly every time I check it, but others will never work…

Here is another recent thread with a lot of hints