Heat pump for KfW55 house 148 sqm

Techn_FAQ point 2.03
For a KfW efficiency house 55 according to reference values, there is a
requirement to install a ventilation system in the
building. This also applies, for example, when installing
central ventilation systems in an apartment building, which must
therefore be installed in at least all apartments.

For KfW55 no ventilation system is required. You can quote whatever you want now ;)
My brother-in-law is currently building a KfW55 single-family house without an automatic ventilation system...

Daniel-Sp no problem, you probably won't be doing any HVAC calculations either,...

Not that, it’s not my profession either. But I calculated the design of my underfloor heating myself and the heating engineer implemented it accordingly. And I had read so much about the subject that I can confidently say that your statement, in its exclusivity, is not correct and therefore I do not understand it.

Have a nice day everyone, I don’t think I have greeted yet today, sorry.

: What do you mean by system now? The one installed at the operator? Or a specific heat pump model?
My Arotherm plus can be operated monovalently, yet I have installed an electric heating rod (bivalent), which does not engage during normal operation, but only at -12°C.
So what do I have?

The problem with the KfW definition is that it indirectly bases itself on the DIN 1946-6 via the VdZ ventilation concept tool, which generally no longer provides for manual ventilation. Clearly industrial lobby.


System = heat generator I speak of system because often the domestic hot water generation is combined with the room heating, possibly also 2 heat generators.
Concrete models are more likely to be found in Austria or Switzerland, where monovalent heat pumps have been installed for a longer time and test data is publicly accessible.
In this country, it rather concerns specific models from Daikin and Panasonic possibly also Lambda.

What you have, you can tell by whether the refrigeration circuit/the refrigerant only exists outside the building. The system concept simply is not the same.
So I have to do other things now, bye

What you have can be seen by whether the refrigeration circuit/refrigerant exists only outside the building.

Ok, I think parcus means something completely different. It may be that in some specialist circles there is a different definition for mono- and bivalent. Something like moment or sufficiently.

This is the case with my Vaillant. And by the way, in my opinion this would be the definition of a monoblock device. Still, I can operate it bivalently. In this respect, you seem to be mixing things up. Or you mean something else, which in your sources is either described as monovalent or is misleadingly described together with the characteristic of a monoblock.

What we mean by bivalent: There are two possible heat generators in the installation. E.g.: heat pump + heating element. Or gas BWT + solar thermal. Or...

Edit: Your definition quoted above is not really sensible from the start, since there are also indoor heat pumps. They would never be monovalent, no matter how the further installation looks…

The line lengths should be indicated for each room in the HVAC calculation, which is why it is called room heating load. That means the heating load like the underfloor heating and the hydraulic balancing are determined for each room. U-values of interior walls, interior wall assemblies,

Maybe it should, but it’s not included. Our HVAC planner can do some great things.

The good thing is: I feel the same and you don’t have to either. I think it is (for the majority) consensus that the heat pump is too big, and I keep my fingers crossed that you somehow come to a better solution.

Thanks, a bit of balm for my soul.

Many thanks also to , through your posts I have understood a lot.

But it doesn’t help, supposedly the 11kW monster will still arrive at the beginning of January.
With that, the offer of credit and removal is also off the table.

The outdoor unit has the model number ERLA11DAW1
Does anyone maybe know how far it can modulate down?

What threatens us with our monster?
More power consumption? How much more?
Increased cycling, faster reaching of heat pump heaven?
What else?

Maybe it will break down within 5 years.
That would be karma.