New condensing boiler heating - radiator thermostats

Hello, since we previously lived in a rental apartment and had nothing to do with the actual boiler, I have no knowledge in this area.

So, well, we bought a house in April and yesterday the old heating system was replaced with a new heating system from Buderus. We had it set so that the house should be heated from 9:00 AM to 11:45 PM with a temperature of about 23 degrees (we have a small child). At night it should be lowered to 18 degrees. Now my question is what role do the valves on the radiators still play. At the moment we have them set to 4, but it is only about 21 degrees in the living room. Do we have to set the valves to 5 in order to reach the intended 23 degrees? That would be the most logical to me. And should we turn down the valves at night before going to sleep (actually not, since the boiler has a nighttime reduction and does this automatically)?!

Thanks in advance!

ps: All thermostats on the radiators were also replaced and the hydraulic balancing was also done.

The heating controls the flow temperature via an external sensor.

And should we turn down the controllers at night before going to sleep

No, actually not. Only set to "Star" for airing out. Otherwise to comfort temperature.

Thank you.

And what about during the day? Should the thermostats be set to 5 so that the intended and set temperature in the boiler is reached?

Does anyone else have any ideas?

Rules the thermostats do not directly control the temperature? Something like 3 = 20 degrees, 4 = 24 degrees. 5 then stands for 28 degrees room temperature.

Without an on-site appointment, one can only guess how things are arranged...