HomeMatic Things Lost Every Now and Then

I’m experiencing some issues with my HomeMatic integration. And it’s strange. I can get it to work sometimes and for a while until it stops working all the sudden.

But let’s step back a bit.


My openHAB installation runs with the following configuration on a Raspberry Pi:

  • Hardware: Model B+ (Revision 0010)
  • Raspbian GNU/Linux 9 (stretch)
  • Linux 4.19.66+
  • openHAB 2.5.1-2 (Release Build)
  • Homematic Binding

On the same RaspberryPi, I’m also running Homebridge 0.4.50.

HomeMatic is running on a CCU 2 (Firmware version: 2.49.18).

They’re both on the same network, connected through the same switch via Ethernet.

I have a bunch of items installed in HomeMatic. They all work seamlessly through the CCU’s web interface and even through HomeBridge. Like all the time. No issues.

Among my items, I have five HmIP-STHD humidity and temperature sensors.

And those are the ones that my OH installation loses the connection to.


When that happens, OH reports “OFFLINE - COMMUNICATION_ERROR” for the things. Oddly enough, it usually doesn’t always happen to the same set of devices.

I don’t really know how to fix this, once this happens. I read on a different thread that just touching the things file would solve this. It doesn’t for me. Rebooting everything usually doesn’t work either – at least not right away. Often times I’ll give up and give it another shot a couple of days later. I can’t really tell you what solves it for me, but my devices usually come back online after a while of just fiddling around and a lot of dumb luck.

I’ve also tried switching from the file-based thing configuration to PaperUI. But this didn’t help either.

Given that Homebridge and HomeMatic work so fine, I’m assuming that it’s got something to do with either OH itself or with the binding.

Does anyone else see this kind of behavior? Is there anything that I’m missing?