Room thermostat with rotary knob from Busch Jäger

Exactly that's what I mean, if I now set 19 degrees in the Unitower and turn a thermostat to level 4 or 5, it can never reach the temperature and the valve never closes and the power would run forever because the heating always stays on?

Well, since no energy enters the house, you’re not really consuming anything. Just the maximum 20 euros per year for the control valves on the heating circuit distributor, and if the heating runs continuously, you only pay 15 euros for the electricity for the valves. So it’s not that drastic.

You have a small misconception.

You think you could control something with the thermostats in the rooms. That’s not the case; they are more decoration on the wall and an emergency brake, provided the heating system is adequately sized and optimally adjusted.

Can’t I just control each room individually via the thermostats then? Apparently I really have a misconception. I think if I now, for example, turn the thermostat to 4 in the dining room, I’ll get about 20 degrees. And in the bedrooms I just want to turn it to 2 or 3 so that I get 15 or 16 degrees. Isn’t that the case?

But that is the case because the thermostats then apparently stop the heat output. But that is not a regulation, rather a choking of the system.

But what are you actually getting at?

I want to know how I can set the temperature via the thermostats so that I have different temperatures in the various rooms. Bedrooms naturally colder than in the bathroom and living area...

You grab one or more thermometers and first set the heating. Turn all the dials to 6 and then after 2-3 days check the temperatures reached in the rooms. Then adjust the heating down/up until the usual 24° is still reached in the bathroom at 6.