Air-water heat pump combined with underfloor heating does not work properly

Yes, exactly, that exists. I therefore disabled the actuators because otherwise I would have to supply them with power continuously to keep them open.

Tolentino mentioned that there are motors that remain open without power. How can one possibly identify which ones are installed? :)

Switch off the power supply to the actuators (common fuse?) and check if the underfloor heating still has flow. Or look for a product name/code on the actuator and google it.

Not necessarily. Of course, you can turn down the volume flow for the bedroom at the HKV until you reach your desired temperature.

Since I am not exactly familiar, I don't know exactly where I need to do something here. Where do I set the volume flow?

Not a bad idea, because there is no switch for this. You actually have to disconnect the cables from the motors. Not everyone just does that.
Step one should be to go to the heating engineer. He should do a hydraulic balancing if it hasn't been done already. Then you can search here or generally on the net for "thermal balancing." This is a topic for several days if not weeks, because a underfloor heating system, as already wrote above, reacts very sluggishly.

I will have to bring that up at the first maintenance.

I don't think so. District heating has a clear advantage and that is the space-saving in the connection room.
Disadvantages are: dependence on a monopolistic supplier, namely:
- Financially
- Technically
As well as higher consumption costs and inefficient heating system.

see above "thermal balancing"
Otherwise, people need to get involved who are more than just well-read laypeople.
Maybe will stop by here again; he knows quite a bit.

Since the air-water heat pump has to switch on the heating element from a certain temperature, which also costs electricity, as well as the additional supply of the towel radiators in the bathrooms, also via electricity, that doesn't sound like a cheap solution either. On top of that, we still don't have a solar system. However, it is planned for the future.

Or take a look in the fuse box: for us, the control valves are separately fused.

Same here.

If your heating engineer and electrician have talked to each other, the actuators are connected to their own fuse switch. Then you only have to remove the fuse and remove the actuators. Saves money over the year as well.

So I always have to get to the heating unit myself and turn it? Since I am an absolute layperson, I am afraid of doing more damage than anything else.

Furthermore, a lot of information is missing. Is there a heat load calculation, room-by-room heat load calculation? Calculation of the heating surfaces (installation spacing, flow rate with NAT), were desired temperatures queried for the room-by-room heat load calculation, was a maximum flow temperature agreed for NAT. I suspect from many reports here from building with a general contractor that this has not happened and at best a pro forma design of the underfloor heating from the floor heating system manufacturer according to the usual scheme with a flow temperature of 35°C.

Such details were not discussed with us. What is a NAT?

What does the hydraulics of the system look like before the HKV? Does the heat pump heat directly into the underfloor heating (optimal situation), is there a heating circuit buffer, and if so, how is it installed. Especially here, there are still many efficiency killers lurking, keyword separating buffer, combination buffer/stratified storage tank, overflow valves.
If you have read up well and are familiar with your system, you will usually manage efficient operation, but you have to let go of the idea that you can really achieve something in each room by a quick turn of the room controller. Heat pump with underfloor heating in a new building means setting desired temperatures for each room (within narrow limits), adjusting and optimizing the system in the first two winters, and only dealing with the heating again when replacing the heat pump hopefully after >15 years.

Honestly, I don't know exactly. From my gut feeling, I would say the heat pump heats directly into the underfloor heating.
Right now, I lack the idea of where exactly I can set desired temperatures per room if not at the temperature controller. Also again directly at the HKV? How do I know how exactly to set the temperature there?

I don't see the decision against district heating as a mistake if you also care about heating costs. District heating in combination with underfloor heating is also a sluggish system in a new building.

Do you have shading at the windows?

Regards

Yes, we do. We have exterior blinds.

How is the house insulated?

A good thermal envelope basically makes large temperature differences inside impossible.

You would then have to insulate the interior walls and that is generally never done.

Unfortunately, not at all. We were badly advised here as well. We only have 24 cm bricks with plaster on top. No additional insulation. At the time, we had no idea and were made to believe that this was sufficient. Today I see it completely differently, but now the cat is out of the bag.

Ugeen, before you regret district heating afterwards, just deal a little with the subject and then I think you will learn to appreciate the advantages of the existing system. You just have to let go of previous habits and the corresponding logic. Afterwards, you will probably experience even better comfort than before.

Maybe that will happen. Among other things, we also decided on the air-water heat pump because we were assured here that the cooling function cools down 6-8 degrees. I could not notice that at all this summer. Here, an air conditioner would probably have been the better solution.

You can clearly see that you should not rely solely on others but rather always actively inform yourself. No one here can meaningfully explain to you what you want to know. First of all, self-initiative is required here, so please google [Hydraulischen bzw. Thermischen Abgleich] in connection with a [Luft-Wasser-Wärmepumpe]. You can then read up for 2-3 days and provide the requested information here and ask targeted questions.

We also decided on the air-to-water heat pump, among other things, because we were assured that the cooling function cools down by 6-8 degrees.

That was definitely bad advice, sorry for you! Realistically, it will be 2-4 °C. Did you even hear about a cooling function? As I recently learned, it also depends on the correct individual room controllers (ERR) that must be compatible with it....

We also moved in at the end of January. We also have an air-to-water heat pump with underfloor heating and photovoltaics. I experimented for about 14 days until I determined the correct supply temperature for the air-to-water heat pump. After that, all ERR are fully on and only the one in the bedroom is "almost" completely turned down. This way, the bedroom does not heat up as much and all other rooms have a consistent, pleasant temperature. The bathrooms also have towel radiators. They only get lukewarm, indeed. But that is enough to dry the towels overnight or during the day. The heating element in my air-to-water heat pump only kicks in at around -15 to -20 degrees. So last winter, it did not activate. The combination with the photovoltaic system works great. Since March, I have hardly drawn any electricity from the grid. Even now, my system still supplies our house 100% autonomously.