Technical comparison of air-to-water heat pump

Thank you very much for your feedback. I will take up the above-mentioned points and discuss them with the paramedics. Since I know both companies and have seen many references, I basically feel well taken care of by both companies and trust that the system will be professionally and technically correctly designed and installed. Can anyone say something about manufacturers iDM and Stiebel? According to my research, iDM seems to be more like the Audi and Stiebel the Golf among heat pumps. However, there is very little information about iDM available on the internet...

Well, the forums are full of people who trusted that the heating installers would do it right. Professionally and technically correct is also a floor heating system with 40 degrees flow temperature. Nevertheless, it is not efficient.

Well, without being able to trust other trades, building a house becomes an even more nerve-wracking matter than it already is. Therefore, I don't want to start a fundamental discussion. No hard feelings! I gladly take note of the points mentioned/am grateful for them and will actively discuss them with the heating engineers and listen to their opinions. What is important to me are the experiences with the iDM or Stiebel, because especially about the former there is little information available online.

If you focus on the heat source at the moment, in this case the heat pump, you are already making a mistake from the start.

The most important thing in a heating system is the heat sink, in this case the underfloor heating.

Anything done wrong here cannot be fixed anymore, no matter how good the heat pump is.

The heating engineer only owes you a heating system that warms the house, nothing more.
Therefore, you or an MEP planner who calculates the underfloor heating according to your specifications must tell him what you expect from the heating system.

And for that, you should definitely read up on the topic of underfloor heating and its design.

Installation distance of 7 cm in the bathroom.

Do not calculate with 20 degrees at room temperatures, rather with 22.

If there is a large bathtub and rain shower, then please more than 200 liters of hot water storage, preferably a fresh water storage but not more than 300 liters.

Why is a fresh water storage better?

Well, the forums are full of people who relied on the heating technicians to do it properly. Professionally and technically correct is also an underfloor heating system with a 40-degree flow temperature. Nevertheless, it is not efficient.

What??!