# Bosch Radiator Thermostat II [+M]

With Zigbee2MQTT, this TRV exposes a writable `pi_heating_demand` entity. _VTherm_ can use it for [self-regulation by direct valve control](https://www.versatile-thermostat.org/en/docs/self-regulation/#self-regulation-by-direct-valve-control). In Matter mode, `pi_heating_demand` is read-only: use the Zigbee mode.

## Limitations

1. About 15 minutes after the last command, the TRV goes back to its own internal algorithm. An automation that sends the last `pi_heating_demand` value again at regular intervals keeps the valve under _VTherm_ control.
2. When turned off, the TRV sets a 5 °C setpoint.
3. Water flows only above about 15 % of opening: adjust the minimal opening to your radiator.

> [!NOTE]
> Because of these limitations, this device is partially compatible.

## Compatibility status

- **Partial**: This device is supported by Versatile Thermostat, but some advanced features may not be supported. Devices: Bosch Radiator Thermostat II [+M]

## VTherm configuration

### Initialization

Go to your settings, then integrations, then click on add a new integration. Search for Versatile Thermostat.

Click on Thermostat over another thermostat.

### Basic attributes

Go to the "Main attributes" section.

1. Choose a name for your thermostat
2. Set the temperature sensor for your room
3. If you are using the Zigbee protocol and you have a "last_seen" entity for your temperature sensor, fill it in.

You can validate and return to the configuration menu.

### Underlying entities

Go to the underlying entities section.

1. Add the thermostats that will be controlled
2. In the auto-regulation section, choose "direct valve control"

You can validate and return to the configuration menu.

## Community references

Additional references may be old. A bug reported on an old version of VTherm may have been corrected on a more recent version.

- [Discussion #1468 Bosch Radiator Thermostat II \[+M\] seems to revert to internal algorithm after 15 minutes](https://github.com/jmcollin78/versatile_thermostat/discussions/1468)
- [Discussion #1003 Bosch TRV will soon be directly controllable!](https://github.com/jmcollin78/versatile_thermostat/discussions/1003)
- [Discussion #1775 Vtherm and Shelly TRV BLU valve opening values not always consistent](https://github.com/jmcollin78/versatile_thermostat/discussions/1775)
- [#334 Endless loop created by turning VTherm with multiple climate devices on and off very quickly](https://github.com/jmcollin78/versatile_thermostat/issues/334)
- [#576 Ignore set temperature changes from underlying if outside of configured min/max range](https://github.com/jmcollin78/versatile_thermostat/issues/576)
- [#1249 Central Mode "stopped" not working](https://github.com/jmcollin78/versatile_thermostat/issues/1249)
- [#533 Percentage of valve opening blocked between 0 and the regulation threshold](https://github.com/jmcollin78/versatile_thermostat/issues/533)
- [#536 Option for Min Percentage of regulation for Thermostat over valve / in addition to delta percentage of regulation](https://github.com/jmcollin78/versatile_thermostat/issues/536)