Heat pump for KfW55 house 148 sqm

Might not help you, but yesterday I accidentally came across heating providers online and was surprised that, for example, Vailliant Arotherm plus VWL75 is listed as relatively cheap and available from stock / directly available. What speaks against it?

With 11kW you can almost heat a new building with 10 residential units. So it is much too large for your calculation! Did the HB really order that or is he telling you what would be deliverable?

Do you know exactly who ordered it? For us, it was such that a planning office (complete idiots) made the heating design and told the plumber which heat pump to order. At that time, he only had the information about what to order. After he built the heating system and did not follow any (bad) specifications from the planners, I would suspect that he would not have ordered such a wrongly sized heat pump if he had known. If your situation is similar, then I would try to contact the plumber and look for a solution with him. Of course, I don’t know if you can get in touch with him.

Maybe this doesn’t help you, but I happened to come across heating suppliers online yesterday and was surprised that, for example, the Vailliant aroTHERM plus VWL75 is listed relatively cheaply and as stock / directly available.
What speaks against it?

nothing speaks against it, all options are being considered.
With Vaillant I still don’t quite get the type designations. How many kW does it have?

With 11kW you can almost heat a new building with 10 residential units. So it’s way too big for your calculation!
Did the builder really order it or is he just telling you what would be available?

If it wasn’t so sad. But exactly that was ordered.

Do you know exactly who ordered it? For us it was such that a planning office (complete idiots) did the heating design and told the plumber which heat pump to order. At that time he only had the information on what to order. After he built the heating and did not follow any (poor) instructions from the planners, I would assume that he would not have ordered such a wrongly dimensioned heat pump if he had known.

If your situation is similar, I would try to get in touch with the plumber and look for a solution with him. Whether you can reach him, of course, I don’t know.

The heat load calculation comes from a TGA office – the heat load calculation is certainly correct, but how he then arrives at 11kW via the Daikin "heating solution navigator" is unclear to us.
The site manager is asking. I wonder if she couldn’t come to the conclusion herself that 11kW is implausible?
The plumber just ordered blindly.
A complete chain of idiots.

We’re building with BT/GC (fluid transitions, depending on what is more advantageous for the company).
So far the company has remained very tight-lipped regarding the heat pump, removing trades, etc. Now they are more open in light of the situation. And then we got the heat load calculation in hand, now all the nonsense comes to light. And of course, everything way too late.
But we can reach the plumber, maybe we can find a solution with him.
There is also a company that installs self-procured heat pumps.
We are looking at various shops to see what is deliverable.

Here are excerpts from the heat load calculation.
The summary of the heat load calculation.

Then picture 2, the excerpt from the heating navigator by Daikin.
There are completely different numbers again; suddenly an outside temperature of -8.6°C is used.

And picture 3
The "solution": the 11 in the middle stands for 11kW

I don’t understand that.

Wärmepumpe.seeker
at the next karma level

The Vaillant 75 delivers 7 (7.5?) kW but can modulate very low. However, with large houses, you have to be careful whether the maximum flow rate is sufficient (it only manages 1270). Delivery times are often inaccurate. My experience from last year. Availability is even worse at the moment....