Sonoff TRV-ZBT Gen2 Zigbee Thermostatic Radiator Valve

Product detailed description

🔥 Heat exactly where you actually are

The Sonoff TRV Gen2 (model TRV-ZBT, also listed as TRVZBT) replaces the standard mechanical head on your radiator and takes over heating control for you. Instead of endlessly turning a dial, you set the temperature to the exact degree, let a weekly schedule run it, and the valve closes on its own when you open a window.

Compared with the first generation it is 38 % smaller, it gained a colour IPS display and a quieter valve mechanism, so you can fit it to a bedroom radiator or into a cramped spot with awkward pipework. It runs on two AA batteries, so no wiring and no drilling are needed.

What the Sonoff TRV Gen2 does in practice

Precise temperature in every room separately. The valve measures the temperature right in the room and meters the flow of hot water into the radiator to hold your target between 5 and 30 °C. You can keep the bathroom at 23 °C, the bedroom at 18 °C and the living room at 21 °C without touching anything. This room-by-room zoning is where the real savings on heating come from.

Three independent heating plans and a weekly schedule. In the eWeLink app you create up to three separate plans (for example „working week", „home office" and „holiday"), each with up to 12 temperature periods per day across a 7-day schedule. The bathroom warms up before your alarm, the temperature drops during the day and the flat heats up again in the evening, all without a single manual step.

Open-window detection. The smart valve can spot a sharp temperature drop by itself and pause heating. If you want full certainty, pair it with the SNZB-04 Zigbee door and window sensor, and it will react to a window that is genuinely open rather than to an estimate from temperature.

External temperature sensor. Radiators usually sit under a window or behind a curtain, where the temperature differs from the middle of the room. The thermostatic head can therefore take its reading from an external Zigbee sensor, for example the Sonoff SNZB-02M, and regulate by the temperature where you actually sit.

Boost, temporary timer and child lock. Boost mode warms the room quickly when you come home frozen. The temporary timer holds a chosen temperature for a set period and then returns to the schedule. The child lock disables the controls on the valve itself, so nobody knocks your settings out by accident.

Valve protection and frost mode. Anti-calcification turns the valve periodically so it does not seize over the summer, and frost protection switches heating on when the temperature approaches freezing, which matters most in cottages and flats left empty over winter.

Up to 6 months of history. In the app you can look back at the target temperature, the actual temperature and when and how long the heating actually ran. That lets you fine-tune the settings from data rather than from a hunch.

Rotate the display to match how the valve sits. A radiator valve is sometimes horizontal and sometimes vertical, and the display would otherwise end up upside down. You can rotate the screen content in 90° steps through four positions, so you read the temperature without bending down to the floor.

Quiet operation, even at night. The gearbox and valve mechanism are designed for low noise, so you barely hear the valve adjusting. That difference matters most in bedrooms and children's rooms, where older heads wake people with night-time clicking.

Stable temperature instead of swings. The valve does not work in an all-or-nothing way. A control algorithm continuously adjusts how far the valve opens based on the difference between target and measured temperature, so the room temperature holds steady instead of bouncing up and down.

Who the valve is for

• Households with a gas boiler and conventional radiators that want room-by-room control instead of one temperature for the whole flat.
• Tenants and people renting: fitting it needs no draining, no tools in the wall, and you simply take it with you when you move.
• Home Assistant, Zigbee2MQTT and SmartThings users who want the valve in their own automations without the cloud.
• Owners of cottages and rental apartments who need remote frost-watch heating and want to warm the place up just before guests arrive.
• Anyone already running a Sonoff Zigbee ecosystem who wants the valve linked to window and temperature sensors already in place.

Use cases

• Cutting the heating bill in a flat: a night setback to 17 °C in the bedroom and automatic warm-up before morning, hands off.
• A bathroom warm exactly for your shower: a short temperature block morning and evening instead of heating all day for nothing.
• Airing the room without wasting heat: the valve closes while the window is open, so you are not heating the street.
• Controlling heating remotely from your phone: warm up the cottage or apartment on the way, not after you arrive.
• Automation in Home Assistant: temperature driven by presence, weather forecast or energy price.
• A child's room without accidental changes: the child lock keeps the settings where you want them.

Key features

• Compact design: 38 % smaller than the previous TRVZBR generation, fits even tight spots.
• Colour IPS display: shows the set and current temperature, mode, heating status and Zigbee signal strength.
• Rotating screen content: in 90° steps through four positions to match how the valve is mounted.
• Three heating plans: three separate weekly schedules you switch between as needed.
• Up to 12 time blocks per day: each plan lets you set 12 temperature periods for every day of the week.
• Open-window detection: automatically from a rapid temperature drop, or by linking a door and window sensor.
• External temperature sensor: use a compatible Sonoff sensor as the reference instead of the built-in one.
• Adaptive control: the valve continuously adjusts its opening based on the gap between target and measured temperature.
• Protective functions: child lock, anti-seize valve protection and frost mode.
• Up to 6 months of operating history: review target temperature, actual temperature and heating activity.

Technical specifications

Protocols and compatibility

• Zigbee: communicates over the Zigbee standard (IEEE 802.15.4) and needs a compatible Zigbee hub or coordinator to run.
• eWeLink: with a Sonoff Zigbee hub you get the full feature set, including heating plans, the external temperature sensor and notifications.
• Zigbee2MQTT: works directly; the manufacturer recommends version 2.12.1 or newer for full feature support.
• Home Assistant (ZHA): works through the ZHA integration. Native support is still awaiting approval, so until it is merged you need a quirk script from the manufacturer's Help Centre for the full feature set.
• Samsung SmartThings: usable with a compatible hub, the manufacturer provides its own SmartThings driver.
• Apple Home via Matter: exposed by a Matter bridge such as the Sonoff Bridge Max, Bridge Ultra or iHost.
• Google Home and Amazon Alexa: through an eWeLink account and a compatible Zigbee hub; temperature setting and operating mode are supported.

Why choose the Sonoff TRV-ZBT Gen2

• The best value in its class: a colour display, external sensor support and three heating plans at a price where rivals offer a plain LCD.
• You fit it yourself in minutes: no draining the system, no electrician, just unscrew the old head and screw on the new one.
• Open to local control: Zigbee2MQTT and ZHA mean your heating keeps working without internet and without depending on a cloud.
• Quiet operation: suitable for bedrooms, where valve clicking at night is a real problem.

Compared with the previous Sonoff TRVZBR (Gen1) you get a 38 % smaller body, a colour IPS display instead of a basic one, screen rotation through four positions, three separate heating plans and up to 6 months of operating history. If you are comparing other brands too, browse the full smart radiator valves category.

Frequently asked questions

What customers say about our store

See all ratings of our store (average 5.0 out of 5)