Solar heat pump / what to watch for in the offer (single-family house, new construction, KFW70)

Hi everyone,

thank you again for the many helpful contributions. Is it allowed to talk about brands here (if there are two to choose from) or is this not welcomed or permitted here?

@Lacos: Do you have an energy consultation?

I can only report from my position...
Over the weekend, I received several documents from my energy consultant, including his recommended configuration:

Key data:

[*]KFW-70 House
[*]Building envelope area: 756.45 m²
[*]Building volume: 1265.72 m³
[*]Heated air volume: 961.95 m³
[*]Usable floor area: 405.03 m"
[*]A/V ratio: 0.60 1/m
[*]Window area: 49.26 m²
[*]currently 2-person household up to max. 5 persons (you have to plan for the future)

Excerpt from chapter 7.1 system description:
Heating

[*]Generation: Central heat generation with brine-water heat pump (annual performance factor 4.4)
[*]Storage: Buffer tank 450 liters for underfloor heating

Hot water

[*]Generation: Brine heat pump 41% coverage and solar domestic water heating 59% coverage
[*]Bivalent storage: 750 liters

Consumers:

[*]Kitchen sink
[*]Dishwasher
[*]2x industrial sinks
[*]3x toilets
[*]4x sinks
[*]2x showers
[*]1x bathtub

I have not had an energy consultation yet. We have not signed anything yet (but soon), so I wanted to get informed in advance.

So I was glad about the previous energy consultation because otherwise, you have no reference point at all. Furthermore, I was able to compare with the shell construction company whether the materials used are suitable for Kfw70 (as a whole). I can also already give the heating installer a document to guide him since I was not familiar with the different sizes (see key data).

Who is creating the KfW application / energy certificate for you?

It is best to have the system commissioned by the factory service as well, because they know best how to operate your system.

Hello everyone,

the energy performance certificate is created by the general contractor - we want to build turnkey.

Thank you very, very much for the numerous comments!
With regard to the heat pump, this one has now emerged. It has an integrated 200l tank, no buffer tank is used for the underfloor heating according to the general contractor.
What is interesting about the heat pump is, besides a cooling function, the touch control and operation via PC / iphoneAPP (the heat pump has a WLAN module ^^)

Lacos