Hi All!
I have multiple Bosch Room Thermostat II in our house. It is connected by Zigbee2MQTT directly, without the Bosch Smart Home controller. Since September the batteries of all thermostats are started draining fast (it lasts 2-3 weeks only). I have already tried reconfiguring, resetting, re-pairing, but nothing helped so far.
Is there anyone using the same thermostat?
If yes, may ask what is a reporting setting for the thermostat and the firmware version?
Thanks for the help in advance!
Not a solution to your particular problem, but rather a caution to anyone with battery-powered thermostats. Our house came with a wired battery dumb thermostat when we bought it 20 years ago. As the battery was wearing out, it unexpectedly didn’t have enough juice to close the relay to turn the heat on. I came home from work to find a cold house, and scared from the thought of frozen pipes and a disaster if I was away from home on a trip when the batteries died. TL;dr it’s thermostats with wired power here ever since…
Absolutely valid.
But in our case the Thermostat is used as an interface only. 
You can set the desired temperature there and that is all. (No relay, not even important as a temp sensor as I’m relying on other temp sensors.)
Your valves might be too hard to close and open.
Usually the pin part that is pushed in to close the valve can be exchanged.
It might help.
Other than that the best advice is to put them on mains power (not directly og course 
)
These are not valves, these are Room Thermostats. And they worked without any issue for more than a year. Then after a z2m migration and OTA update it started to drain.
Now I’m investigating what is causing this issue. (Can be a firmware bug also.)
Ahh, but a connection to mains power will still solve it
True.
If I would have the possibility, I’d took the 230v type ones.
But we are on track, at Zigbee2MQTT it is already being investigated.
It can easily be done with a few parts.
The wood pieces are just for filling the gap in the battery compartment of your device, so it should have about the same diameter as a battery and the length should be a bit below the length of a battery. The screw can be used to fit the correct length.
The pictured screw head might be too big for some battery compartments, because the plus point is only the space of the top of the battery, but that is just a question about finding the right screw.
The only missing parts is an old USB charger (1A is usually more than enough) and some wire, and maybe some soldering (I crimp them in dupont connectors instead for the connection to the USB module and just wrap it tight around the screw).
Hey @WallyR,
Yeah it would be a valid idea, but I don’t have power source near the thermostats. That is why I choose battery operated ones. And these were quite good for almost 2 years, but now something happened.
We just need to find out what. (Z2M change or the firmware…)
Well, happy hunting.
Just for the record, if anyone bumps into this.
It looks like a firmware issue with the latest firmware on these thermostat. Bosch is aware of it… (Since the summer 
)
Relevant links:
