Radiator thermostat II - boiler controll

[vrzi]

I'd like to buy a Radiator Thermostat II and put it on all the radiators. But I also need to control the gas boiler.

Is it possible to use a relay (for example Bosch smart home relay) to automatically control the boiler?
To make it work like this: If the target temperature in any room is higher than the actual room temperature, the relay will switch on the boiler, if the target temperature is in all rooms, the relay will switch off the boiler.

[Maurice · Accepted solution]

Unfortunately, it's not that easy. The smart relay can control a boiler, but the radiator thermostats can't control the smart relay. That's only possible with a room thermostat.

A workaround with automations is also impractical since these have no read access to the current target temperature.

Don't get me wrong, what you wish for makes sense and you're not the first one to ask. The system unfortunately lacks this feature though.

[vrzi]

Thanks for the information, I was hoping to replace the Honeywell EvoHome system. I would like to reduce the number of smart home systems in my home, but there isn't one that has all the features I need.

[vrzi]

Do I understand correctly that it is also not possible to use the Smart Plug Compact?

[Maurice]

Unfortunately no. The issue is that the radiator thermostats can't control anything but themselves. There are many ways to set the target temperature, but there are no features which would allow to perform any actions when the target temperature is higher than the actual temperature or when the radiator thermostats open the valves. This information is available to the controller, it just can't be used in any meaningful way.