Cooling with heat pump via underfloor heating?

I always find the argument "Summer is only 3 months and sometimes it rains" absurd. Summer still comes every year, I don't want to spend a quarter of my life in terrible discomfort just to make that argument, do I? So we are already very curious about the first summer with air conditioning. I spent several weeks of 35-40°C in 2019 heavily pregnant and I never want to experience that again. A comfortable temperature is a piece of quality of life for me. The extra cost for the air conditioning was about 5k for us, which I would have gladly saved somewhere else on the house corners if necessary. But not everyone has to see it that way, I just absolutely don't like it when I'm too hot. Vacation in Crete is nothing for me either. :P

Last year we had a maximum of 24 °C in the bedrooms despite partial south-facing exposure. That is still bearable. In summer we make sure to operate the roller shutters accordingly. Nevertheless, it would be comfortable to have at least some ventilation in the bedrooms.

I always find the argument "Summer is only 3 months and sometimes it rains" absurd. Summer comes every year anyway, I don't want to spend 1/4 of my life in terrible discomfort just to argue that way, do I?
So we are really looking forward to the first summer with air conditioning. In 2019, I spent several weeks of 35-40°C being heavily pregnant and I never want to go through that again. A comfortable temperature is a piece of quality of life for me. The extra cost for the air conditioning was about 5k for us, which I would have gladly saved somewhere else on the house if necessary.
But not everyone has to see it that way, I just really don't like it when I'm too warm. Vacation in Crete is also not for me. :P

1. During the 3 months, it's hot for a maximum of 6 weeks. You can ventilate the rest.
2. Without air conditioning, the house also had a maximum of 26 degrees even when it was 40 outside.
3. Today's youth vote Green, but then install air conditioners so they don't sweat.

1. In the 3 months it is hot for a maximum of 6 weeks. The rest of the time you can ventilate.
2. In the house, even without air conditioning, it has a maximum of 26 degrees for us, even when it's 40 outside.
3. Today's youth vote Green, but then install air conditioners so they don't sweat.

Almost right:
Vote Green, install air conditioners to make the damage caused by 20 years of voting Black bearable, and then run the air conditioner with the photovoltaics on the roof. :cool:

I would fundamentally distinguish between "opinions" and "experiences" - unfortunately, this is not clearly apparent in many statements in this thread.

Here is an EXPERIENCE report, based on:
- own house: air-water heat pump (Viessmann) with active cooling function via underfloor heating
- parental home: air conditioning

[*]My conclusion based on the specific example:
summer day without active cooling: temperature in the attic at 28 degrees. When I activate the cooling, I get down to 24 degrees (less is difficult due to condensation on pipes). For me as a person sensitive to heat, this makes the difference to be able to sleep comfortably in the attic. The PERCEIVED reduction in heat load is significant!
The function is therefore excellently suited to avoid heating of the interior rooms despite high outdoor temperatures.
[*]Pro compared to air conditioning: very pleasant coolness, no dry air
[*]Con compared to air conditioning: the interior rooms do not get really cold/fresh. On a typical summer day it stops at 23/24 degrees. Those who want lower temperatures need the air conditioning.

In summary, a clear recommendation for the cooling function

Thank you! You describe your experience starting from 28°. Do you also have experience with cooler starting temperatures (that is, how far can you go down from, for example, 24°)?