Heat pump is not compatible with a water-bearing fireplace

Hi,
Is the radiator operated from the same mixing circuit as the underfloor heating or does it have its own mixing circuit?

Well, I would still expect to be able to temperature my individual rooms differently with a heating system, no matter the type. Who would want the same temperature in the bedroom as in the bathroom?

Especially with such a high-priced investment.

In this particular case, the entire concept of the heating system must probably be reconsidered. But the main thing is the heat pump.

It will probably only be operated at night with clean green electricity from the [Photovoltaik Anlage].

That has nothing to do with the heat generator at first. The heat distributes itself within the thermal envelope, especially when the room doors are open. If you want a room to be particularly warm or cool, you have to isolate it from the others. A few degrees K difference is possible, but 18 °C in the bedroom and 24 °C (or more) in the adjacent bathroom will be difficult. This applies all the more the better the house is insulated.

This has nothing to do with the heat generator at first. The heat spreads within the thermal envelope, especially when the room doors are open. If you want a room to be particularly warm or cool, you have to insulate it from the others. A difference of a few K is possible, but 18 °C in the bedroom and 24 °C (or more) in the adjacent bathroom will be difficult. This applies all the more the better the house is insulated.

That is only partly true.
I have 24° in the bathroom and next door in the bedroom at most 18° (except in summer).
In the living room I have a slightly higher temperature than in the kitchen, even though there is no wall in between.
This works with radiant heat.

We decided against the towel radiator and manage just fine without it. I also don't understand what you all do in the bathroom that requires it to be 24 degrees. You don't stand around naked forever, you dry off and get dressed, right?

We never had it on anyway :)

Technically, it was required. It hangs on the wall behind the door and doesn't bother anyone. It also didn't cost a fortune.

That exactly describes the problem.

The builder who is now building new often doesn't even know the difference between convection and radiant heat. He comes from an apartment with radiators and then has to realize how differently the underfloor heating heats.

There is simply no direct heat source anymore. In the past, he could turn up the radiator thermostat and five minutes later the room temperature would be a few degrees warmer. Of course, that doesn’t work with a heat pump underfloor heating.

But not everyone likes it. Personally, I don’t either. I always have warm feet and I don’t like that constant heat from below.
It is also said to promote the formation of varicose veins and similar issues. So underfloor heating is not always beneficial health-wise.
In the bathroom I of course like it very much and it also makes sense there. In the kitchen I don’t need it.

And just installing a heat pump with the associated underfloor heating in the new building because it’s standard and everyone else does it, I don’t consider to be a good approach.