Ho appena acquistato 5 Valvole TRVZBT 2nd gen ma ho un problema che si verifica in maniera random con le valvole, in pratica la valvola si disconnette dall’hib zigbee e quando premo pulsante fisico richiede di fare nuovamente calibrazione, poi si riconnette in automatico alla rete. Succede a turno con tutte le valvole…si tratta di un bug?
Several users have reported the same behaviour with the TRV=ZBT 2nd gen: random disconnects followed by a forced recalibration when the valve wakes up again. So yes, this pattern is already known and looks firmware‑related. I’m monitoring information about the TRV-ZBT because I’m considering buying another valve to complement my current TRVZB units. Meanwhile, IKEA has just announced the LILJEBAGGE — a Matter‑over‑Thread thermostatic valve for hydronic radiators. Its price is impressively low!
Before assuming it’s a bug, though, it would help to check your Zigbee network. It’s unlikely that all valves are sitting right at the edge of signal quality, but it’s still worth verifying.
Can you share details about your Zigbee setup = coordinator model, Zigbee channel, number and placement of routers, and the LQI/RSSI values for each valve?
If the network looks healthy and the valves still disconnect and recalibrate, then it’s almost certainly the same issue other users have been reporting.
Thanks for your detailed reply and for the information.
Regarding your questions, the valves are managed through an NSPanel Pro 120. I never experienced this issue before when I was using the 1st generation TRVZB valves.
Also, all the valves are well within the Zigbee coverage area, so I don’t think signal range is the issue. The fact that the problem started with the 2nd generation valves, while the 1st generation ones worked reliably on the same setup, makes me think it could indeed be related to the firmware or to the new generation of the valves.
Thanks, that’s very helpful. The fact that the 1st gen TRVZB valves were stable on exactly the same setup is actually quite interesting and makes a firmware/device-specific issue seem more likely.
Just out of curiosity, do you know whether the 2nd gen valves usually connect directly to the NSPanel Pro or through other Zigbee routers? And if you happen to have an LQI/RSSI reading for one of the affected valves, I’d be interested to see it.
The valves are connected directly to the NSPanel Pro 120, and the issue occurs with all five TRVs.
The RSSI signal is also very good, ranging between approximately -50 and -60 dBm, so I would not expect the problem to be related to poor Zigbee coverage or signal strength.
Just one more question, just to rule out the network topology as well: do you have any mains-powered Zigbee devices (switches, plugs, relays, etc.) in the same Zigbee network, apart from the NSPanel Pro?
I’m asking because mains-powered Zigbee devices normally act as routers/repeaters, so they can extend the network and the TRVs may be able to use them even if the eWeLink interface shows the valves as connected to the NSPanel Pro.
Also, there is a simple test you could try with just one of the affected TRVs: temporarily remove the TRV from the radiator and place it somewhere close to the NSPanel Pro, ideally just a couple of metres away.
The purpose of this test would not be to check the normal operation of the valve after removing it from the radiator. Obviously, the TRV may behave strangely when it is no longer mounted on the valve body. The only thing we would be testing is the stability of its Zigbee connection and whether it still disconnects and triggers the recalibration procedure.
It’s not a perfect test, but it should be a quick way to eliminate radio conditions as a factor. If it still disconnects and recalibrates even with the TRV placed close to the NSPanel Pro, that would be a pretty strong indication of a device/firmware issue rather than a coverage problem.
I’m not assuming that signal strength is the problem - I’m just trying to eliminate the network side of things before blaming the firmware.
Thanks again for your suggestions.
Regarding the Zigbee network, the only other Zigbee device I have apart from the TRVs and the NSPanel Pro is an SNZB-02D temperature and humidity sensor.
As for the test you suggested, one of the TRVs experiencing the problem is already located very close to the NSPanel Pro, at approximately 1.5 metres away. Since I installed the valves about five days ago, this particular TRV has already experienced the disconnection and recalibration issue three times.
Considering how close it is to the NSPanel Pro, I think this makes a coverage or signal-strength issue quite unlikely. This is also something I never experienced with my previous 1st generation TRVZB valves using the same setup.
So at this point, I’m also leaning towards a device or firmware-related issue.
Given your setup, you have a very (!) minimal Zigbee network - essentially the NSPanel Pro as coordinator with several battery-powered end devices and no additional Zigbee routers.
In such a minimal configuration, short distance doesn’t necessarily guarantee stability, but the fact that all five TRVs show the same repeated disconnect + forced recalibration pattern strongly suggests a device/firmware issue rather than simply poor coverage.
I suggest opening a support ticket with Sonoff and providing them with these details. At this point, I don’t think there’s anything particularly clever or better that we can come up with ourselves. The fact that the 1st-gen TRVZBs worked reliably on the same setup would be worth mentioning.
I feel like suggesting you not to worry too much about 2nd gen TRV-ZBT instability. Winter 2027/2028 is still far away and I’m sure SONOFF will fix all current and future bugs by then. Meanwhile feel free to suggest SONOFF all of the features you would like to see implemented in them. They take real care of us users and will be glad to develop a 3rd gen TRV with new mind blowing user suggested features. As for winter 2026 let’s stick with first 1st gen unjustifiably less featured TRVZB.
Indeed! Let the users spend the next couple of years testing Gen 2 and suggesting the “mind-blowing” features for Gen 3. 
Perhaps Gen 3 will finally do something truly revolutionary - knit a sweater and make a cup of Irish coffee whenever it loses its Zigbee connection. Now that would be a useful feature!
So yes, for winter 2026, let’s stick with the “unjustifiably less featured” 1st-gen TRVZBs. Sometimes fewer features is actually a feature.
I am experiencing the same issue. I am using a NS panel pro gen 2 as my main ZigBee gateway but have around 10 ZigBee routers in my house so I’m sure the issue isn’t signal related. Also all TRV’s are showing good signal. I have reported the issue to sonoff and am awaiting feedback
Thank you all for sharing your real-world experience. Regarding reports that a small number of users may occasionally see a calibration prompt again during use, we have further addressed and improved related operating stability in the v1.1.0 firmware, released on September 7.
We recommend updating to the latest firmware and then monitoring the device’s performance. eWeLink users can update directly through the eWeLink App. For Home Assistant users, we have also submitted the OTA firmware to the official Z2M and ZHA repositories:
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Z2M: PR #1301
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ZHA: Issue #257
seems solved with the latest firmware!