For a fully wired solution, the thermostat functionality within the Velbus glass panels is really good.
There is a great binding for openHAB which gives full access to the thermostat.
All you’d need is a glass panel in each room and a channel of a relay to activate the valves.
If you’re lucky enough to have suitable TRV valve bodies on your radiators, you can replace the dumb actuator heads with
24vdc or
220vac wax thermal actuators, just like the ones used on under floor heating manifolds.
If you use 4 wire actuators instead, you can connect them to the heat call of your boiler, so that your boiler will only come on when a valve is fully open.
IE.
Thermostat controls the valves
The microswitch in the valves control the boiler.
If you have a interlock relay between the actuator switches and the boiler heat call, you can easily configure a daily valve movement so that your valve pistons don’t stick during the summer, without the boiler being fired.
If you don’t have any intention of controlling anything but heating, it’s a simple process to create actions for the buttons on each glass panel to affect its own thermostat.
For example.
If you choose the bottom of the range single button glass panel Black or White, with or without programmable back lights, you can program the button to put it’s thermostats into a boost state (until the next timed event or for a pre-defined time).
We have done this for a (public venue) client who didn’t want a thermostat that could be tampered with.
However, they did want an easy way to boost the heating for each zone.