Cooling with heat pump via underfloor heating?

Your discussions about the installation options of the air conditioning are certainly sensible and helpful for others. Wouldn't it be better to conduct them in one of the air conditioning threads? This thread is actually quite good for getting into the topic of cooling with underfloor heating and heat pumps. (da helfen Erfahrungsberichte von Klimaanlagenbesitzern auch nur bedingt)

Maybe the technology is more advanced than a few years ago. But I once had an office like that and it ended with the ladies sitting under the desk in winter with an electric fan heater, the gentlemen were rather too proud for that ;-) In short: it didn't work at all. The architectural firm was also sued because of these and other planning errors, but then went bankrupt....

We have concrete core cooling or thermal building component activation in the supporting, freestanding columns in the office.
Although I haven't been there for 1.5 years, 22°C in summer was fantastic.

Yes, but only if there is an imbalance. If moist air is already coming in, then it cannot regulate anything. Moist air out -> through the moist enthalpy exchanger -> new moist air in. Result in summer -> moist air everywhere.

I'm not an expert, but shouldn't there be a distinction between relative and absolute humidity? The latter is the relevant quantity for the diffusion processes in the enthalpy heat exchanger. When I look at the absolute humidity for 30°C and 24°C at 70% relative humidity in the hx diagram, there is definitely a difference. That's why the more humid warm outside air transfers its moisture to the outgoing exhaust air. At least, that's my layman's understanding. In the pink forum and the green forum from Austria, you can surely get this explained to you in detail.

Summarizing for me, on the one hand, it is discussed whether cooling via the underfloor heating brings a temperature difference of 2-3 degrees or then actually a full 4 degrees and is therefore a cost-effective alternative to a real air conditioner from a cost-benefit perspective. Or whether only the air conditioner cools in hot summers and noticeably dehumidifies the air.

For me, the discernible calculation formula from the discussion is: In a hot summer with an outside temperature of 37 degrees, every degree Celsius costs a thousand. Cooling via underfloor heating with 2-3 degrees thus costs 2,000-3,000 EUR (in one post even 4,000 EUR), the air conditioner over 13-16,000 EUR. Whoever feels comfortable at 33-35 degrees indoor temperature is satisfied with the 2-3 thousand EUR, whoever would like 21-24 degrees must put a five-digit amount on the table for cooling their single-family house. But these will always be two different things, both in terms of effect and price. Comparing both, I find is nonsense.

Who then feels comfortable at 33-35 degrees indoor temperature,

Now don’t exaggerate!

is nonsense

I agree...

Now don't exaggerate!

what would be the realistic indoor temperature of a Kfw 40/55 house after two weeks of a heat period for you? ;)