Sonoff has released a significant firmware update for its TRVZB Zigbee Thermostatic Radiator Valve, introducing a “Smart Temperature Control” feature. This update (v1.4.4) moves the device away from basic binary switching to a more sophisticated PID (Proportional-Integral-Derivative) algorithm.
What’s PID and How Does it Work?
Previously, the Sonoff TRVZB operated on a simple “On/Off” logic: the valve would fully open when the room was below the target temperature and fully close once that target was hit. This often led to temperature overshooting and inconsistent room climates.
With the new firmware, the valve dynamically adjusts its opening percentage:
- Rapid Heating: When the current temperature is far from the setpoint, the valve opens fully.
- Precision Throttling: As the room approaches the target temperature, the valve gradually closes to prevent overshooting.
- Maintenance Mode: Once the target is reached, the valve fine-tunes its position to maintain a stable temperature rather than shutting down completely.
The SONOFF TRVZB’s transition from basic binary switching to a dynamic PID algorithm allows the valve to intelligently throttle its opening based on real-time heat demand. By gradually reducing the opening as the room approaches its setpoint (rather than slamming shut only after the target is met), the update eliminates the common issue of temperature “overshooting.”
For the user, this results in a significantly more stable and comfortable room climate, while simultaneously boosting energy efficiency by preventing the radiator from running at full power longer than necessary.
How To Update TRVZB Valve Firmware
Platform support for the new PID feature is rolling out in stages. As usual, Zigbee2MQTT (Z2M) users already have access to the update file via OTA. Here is the list of all official platform you can use to update the Sonoff TRVZB to version 1.4.4 or later:
- Zigbee2MQTT
- Sonoff ZBBridge-P (V3.0.0)
- Sonoff ZBBridge-U (V1.18.0)
- NSPanel Pro (V4.4.0) (Beta)
- iHost (V2.10.0)
Firmware upgrades are currently not supported directly through ZHA. SONOFF has submitted the necessary materials to the Home Assistant team and is awaiting approval for native OTA support. You also need a custom quirk applied in ZHA to fully utilize the TRVZB in Home Assistant.
You can get the Sonoff TRVZB on Amazon DE, Amazon UK, Amazon NL, Amazon FR, Amazon IT or Sonoff Website.
That’s cool, do you have any idea if there is any other TRV from AliExpress that supports PID? I’m looking for Zigbee solution but the Sonoff one is more expensive than other vendor
I don’t think you’ll find many Tuya TRVs that supports PID at the moment.
Perhaps something from Moes, though I’m not sure.
Just look for sales on Ali, they can be bought for roughly the same price as the e-waste TRV-s. Don’t make the same mistake as I did, and buy twice.
I replaced almost all my Moes TRVs because of a design flaw. They worked fine for a year or two (I had 11) but the 3 little plastic bits that keep the two parts of the TRV together were gradually bent by the pressure applied by the mechanical valve pin. Some would never shut the valve completely as a result, others broke in two part altogether. I have had the Sonoff ones for a few months and they work great, and because of their better design will never suffer from the same issue.
Honestly for the price, I doubt you will find anything better than the Sonoffs, they are already one of the cheapest ones.
Question regarding this new update:
Is there a way to disable PID and revert back to binary mode on the new firmware?
Yes, you can simply turn off the mode in Zigbee2MQTT
Hello, thanks for the update! I’ve been using Better Thermostat successfully to fix this issue. Do you think there’s an advantage to doing it this way?
I’m not sure how Better Thermostat works, but I doubt it’s true PID
hey Pedro, I am using also Better Thermostat with the “AI” function and a external sensor, but i think it does not work perfectily. Sometimes even setpoint is 21.5°C and the actual is 19.x°C it does not want to start heating for 1-2h. So I am not that setisfied with just the better thermostat. But I thought to use better thermostat just to take the temperature value from the external sensor and then use the PID from the sonoff to do it. Maybe we can solve our problems together.
How to enable “Smart Temperature Control” via Z2M after the firmware update?
The Sonoff documentation states that it is disabled by default: “The feature is off by default and can be turned on as needed in the eWeLink app under “Adaptive Mode”.”
https://sonoff.tech/en-de/blogs/news/trvzb-upgrade-smart-temperature-control-for-more-stable-room-temperature
You need to update the firmware via OTA first and enable the
smart_temperature_controlbinary property, all the way at the bottom.After updating Z2M from 2.8.0-1 to 2.9.1-1 the missing control is finally there 🙂
Us there a link with the burner too? To turn that on when the valve is open?
How can I check if the PID is actually working? The head doesn’t provide a parameter for the current valve opening degree.
I’ not sure, I haven’t tested it yet.
I would start by comparing graphs for a couple of days, with and without PID enabled.
You should less intense swings up or with PID enabled.
I’ve been using two sonoff trv in same room with virtual thermostat and an external temperature sensor and the via automations changing the valve opening degree to override the binary setting. Wonder if this would be a even more stable. Anyone testing something similar?