SONOFF
SONOFF TRVZB Zigbee Thermostatic Radiator Valve
- Zigbee
Verified September 2026
The budget king for Home Assistant TRVs: around £22 a radiator versus £60+ for the Bosch Radiator Thermostat II, with equally solid Zigbee2MQTT/ZHA support and no hub or cloud dependency. The trade-off is build quality and running costs — three AA batteries typically last only around six months (versus roughly two years on the Bosch), and the plastic body and motor feel noticeably cheaper. Fits M30x1.5mm valves directly, with adapters in the box for Danfoss RA/RAV/RAVL, Caleffi, Giacomini and M28. Best suited to whole-house rollouts on a budget rather than the one or two rooms where you want set-and-forget accuracy.
In Home Assistant
| Control | Type | What it does |
|---|---|---|
| Target temperature | Number (4-35°C) | Set the heating setpoint |
| Mode | Selector (off/auto/heat) | Choose the operating mode |
| Temperature calibration | Number | Offset the valve's own reading against an external room sensor |
| Window detection | Binary sensor | Flags a sudden temperature drop consistent with an open window |
In Auto mode Zigbee2MQTT locks the setpoint UI to a default 16°C, which trips people up expecting a schedule mode — use the local_temperature_calibration entity instead, offsetting the valve's own reading against a separate room sensor so it heats to actual room temperature rather than the radiator-adjacent internal probe (a published HA community blueprint does exactly this). External-sensor selection has also been reported to spontaneously flip between sources, so worth a periodic check if calibration seems to drift.
Specs
- dimensions
- 59.4 x 59.4 x 95 mm
- battery type
- 3x AA (LR6) alkaline, not included; ~6 months typical life per SONOFF (shorter than Bosch's ~2 years)
- zigbee version
- Zigbee 3.0
- temperature range
- 4-35°C setpoint range (rated operating environment -10 to 50°C)
- valve adapter compatibility
- Fits M30x1.5mm valves directly; adapters included for Danfoss RA, RAV, RAVL, Caleffi, Giacomini and M28x1.5mm