Replacing thermostat with a ZigBee relay with modulation?

I’m doing some renovation at my place and I have no nice place to put back the thermostat.

I was thinking about replace the thermostat all together with a relay so I can turn it on or off depending of the temperature and valve in all my rooms.

The only problem is that I have a quite new gas boiler and I can modulate how fast it heats up but I can’t find a relay where I can control the voltage.

Does anyone have a recommendation of relay that allows me to modulate the voltage or even a ugly thermostat with ZigBee support that I can keep in my boiler room (that is able to modulate)?

(I live in Europe)

I found a alternative way with Plugwise Adam. I’ll give it a try.

What I learned so far:

  • Plugwise Adam need a thermostat, you can’t control it directly
  • The modulation is done by the boiler not thermostat. You can just set the water temperature and the boiler will make sure the temperature is reached
  • OpenTherm Gateway is the only device I found that allow me to control the boiler without a thermostat