Bosch
Bosch Smart Home Radiator Thermostat II
- Zigbee2MQTT / ZHA
- Local control
- Zigbee
Prices verified September 2026
See more thermostats & heating picks on our Amazon storefront →Our verdict
At around £60-£68 it costs roughly double a SONOFF TRVZB, but you are paying for build quality: precise +/-0.5C regulation and a sturdy valve motor. Bosch quotes under 30dB, and it is quieter than most Zigbee TRVs, though still audible in a silent room rather than truly silent — light sleepers may notice it overnight. It pairs directly with Zigbee2MQTT or ZHA (model BTH-RA, via the QR install code), no Bosch controller required. Fitting is straightforward: it threads onto standard M30x1.5mm valves directly, and ships with Danfoss RA, RAV and RAVL adapters for older UK radiators. Best suited to living rooms and hallways where accuracy matters more than absolute silence.
What can Home Assistant control on the Bosch Smart Home Radiator Thermostat II?
| Control | Type | What it does |
|---|---|---|
| Target temperature | Number (5-30°C) | Set the heating setpoint |
| Valve position | Sensor (0-100%) | Live heating demand / valve opening |
| Boost heating | Switch | Fully open the valve for 5 minutes |
| Remote temperature | Number | Feed in an external room-sensor reading instead of the body-mounted probe |
Zigbee2MQTT exposes a climate entity with heating-demand (valve %) and running-state, plus child lock, window detection, boost-heating and a remote-temperature number input for feeding in an external sensor reading. That remote_temperature value needs pushing at least every 30 minutes or the TRV quietly reverts to its own less-accurate body-mounted probe — worth automating as a push every 15-20 minutes if you want it acting as a true external-sensor thermostat.
Specs
| dimensions | 87 x 51 x 51 mm (L x W x D) |
|---|---|
| battery type | 2x AA (LR6) alkaline, ~2 years typical life |
| zigbee version | Zigbee 3.0 (model BTH-RA, Zigbee ID RBSH-TRV0-ZB-EU) |
| temperature range | 5-30°C, ±0.5°C accuracy |
| valve adapter compatibility | Fits M30x1.5mm valves directly; Danfoss RA, RAV and RAVL adapters included in box |
How does the Bosch Smart Home Radiator Thermostat II compare?
| Product | From | Protocol | Local control | Integration |
|---|---|---|---|---|
| Bosch Smart Home Radiator Thermostat II (this product) | £65.01 | Zigbee | Yes | Zigbee2MQTT / ZHA |
| Aqara Floor Heating Thermostat W500 | £69.98 | Matter, Thread, Zigbee | Yes | Native |
| Aqara Radiator Thermostat E1 | £54.98 | Zigbee | Yes | Zigbee2MQTT / ZHA |
| Aqara Radiator Thermostat W600 | £49.99 | Matter, Thread, Zigbee | Yes | Native |
Frequently asked questions
- Does the Bosch Smart Home Radiator Thermostat II work with Home Assistant locally?
- Yes. The Bosch Smart Home Radiator Thermostat II is controlled locally in Home Assistant through Zigbee2MQTT or ZHA, so it keeps working if your internet connection or the Bosch cloud goes down. Control and state updates stay on your own network.
- Which protocol does the Bosch Smart Home Radiator Thermostat II use, and do I need a hub?
- The Bosch Smart Home Radiator Thermostat II uses Zigbee. To pair it with Home Assistant you need a Zigbee coordinator (for example a SkyConnect/ZBT-1 or Sonoff dongle) attached to your Home Assistant host. Bosch's own hub is not required when you integrate through Zigbee2MQTT or ZHA.
- How much does the Bosch Smart Home Radiator Thermostat II cost in the UK?
- The lowest price we have listed for the Bosch Smart Home Radiator Thermostat II is £65.01 at Amazon UK. Prices were last checked in September 2026 and change often, so confirm on the retailer's page before buying.