Cooling via underfloor heating with brine heat pump

The costs for the pump amount roughly to about 10€/month; it is just a drop in the bucket in every respect.

The cooling capacity of underfloor heating is about 20-30W/m2. To effectively cool an average house, you need approximately 100 Watts/m2.

I think one must clearly distinguish here between a) cooling in the true sense and b) preventing even greater heating.

For a) you need an air conditioning system and b) can be ensured at very low costs with a brine heat pump. As someone else had already written: it does make a difference for well-being whether the average room temperature rises to 26° or only 23/24°C.

Apart from that, I see a positive perception effect in the "cooling" through the underfloor heating pipes. Since the floor radiates cold rather than heat as the outer walls do, one can also perceive the 23/24°C room temperature as cooler?

Yes, when the air is drier.

that is why there are people here in the forum who remove their enthalpy exchanger from the controlled residential ventilation in summer in order to keep the air in the rooms drier than with the enthalpy exchanger. This then completes the plan of "cooling" with underfloor heating through the brine heat pump?

No, because air from outside can also be humid. Therefore, you are not adding additional moisture to the air. An air conditioner dehumidifies.

These are all measures

I think one clearly has to distinguish here between a) cooling in the true sense and b) stopping the even higher heating up.

For a) you need an air conditioner and b) you can guarantee this at very low costs with a brine heat pump.

a) Yes
b) No

As someone else already wrote: it does make a difference for well-being whether the average room temperature rises to 26° or only 23/24°C.

Only if everything really, truly fits. Are the 2° possible? That means with shading, cooling via underfloor heating, with controlled ventilation (or window ventilation) only at night with few windows on the south side, etc.

Realistically, you achieve 1° of cooling, and that really isn’t worth mentioning.

rick2018 has been explaining all along what the problem is. It is the moisture content of the air.

That's why there are people here in the forum who remove their enthalpy exchanger from the controlled ventilation in summer, to keep the air in the rooms drier than with the enthalpy exchanger. That complements the plan of "cooling" with underfloor heating through the brine heat pump?

The air can only become drier if it is dehumidified; what people do with the enthalpy exchangers is rather to be attributed to homeopathy. The air comes from outside with a certain humidity—if it is not dehumidified inside, then it does not matter which heat exchanger is installed.

Air, like everything else, has the habit of wanting to establish an equilibrium between inside and outside, and this state will be reached sooner or later. By the way, the possibilities of a controlled ventilation system (in terms of cooling effect) are just enough to compensate for a television. If you dare to cook in the kitchen in summer, all your efforts are in vain.