ᐅ Are chilled ceilings a practical alternative to air conditioning?

I am not familiar with the "other" system. However, I know the problem of German summers: humidity. If the system cannot reduce it, it can only serve as a supplement to a traditional air conditioning unit.

Thank you all, this confirms my initial assumptions. I think we will stick with the traditional air conditioning system, like the one currently installed in the house. In summer, doors are often left open when guests are visiting and people are going in and out.

Especially then, you might want to cool down specific areas after having let in warm air. I also really appreciate the humidity control provided by our AC.

Building without air conditioning is not an option, especially since we have already become accustomed to the improved quality of life it offers. Considering the latest report from the Intergovernmental Panel on Climate Change (which was somewhat overshadowed by the war), I believe the number of days with extreme temperatures will only increase. :/

I need to bring this up again.
We are currently in the planning phase. We have decided against chilled ceilings for now and instead plan to install a central ventilation system in the house. In addition, my husband still wants an air conditioning system.
We are now considering how to size this properly. In our old house, we had a Mitsubishi outdoor unit with 7100 W (24,000 BTU) capacity connected to three split units: one upstairs in the hallway covering the entire upper floor, one downstairs in the living/dining/kitchen area, and another downstairs in the office.

The old house had 152 m² (1,635 sq ft) of living space, and that setup was sufficient. But for the new house with 215 m² (2,315 sq ft), that probably won’t be enough, right?
Are there air conditioning systems that work through the ventilation ducts installed in the house? That would be convenient since there are ventilation grilles in every room anyway. However, I have read that the low airflow rates in such systems are not sufficient for proper air conditioning.
So, is it safe to say that split units are unavoidable?

How important it is for you to have many indoor units is something you need to decide. For me, one per floor with open doors is sufficient.

However, the capacity is definitely too high. Why would you need more cooling capacity than heating load? A 5 kW heat pump is enough to cover a delta-T of 30°C (54°F), so why would you need 7 kW or more for a delta-T of 10°C (18°F)?

In new construction, a 2.5 kW unit located centrally should be completely adequate. It can then run efficiently for 12 to 24 hours at 250 watts, keeping the entire house comfortable.

Just like with heating systems, you want to avoid short cycling with air conditioning as well.

Deliverer schrieb:

So how important it is for you to have many indoor units is something you need to decide. For me, one per floor with open doors is enough.
But the capacity is definitely too high. Why would you need more cooling capacity than heating load? A 5 kW heat pump is enough to cover a temperature difference of 30°C (54°F), so why would you need 7 kW or more for a temperature difference of 10°C (18°F)?
In a new build, a 2.5 kW unit placed centrally should be completely sufficient. It can then run continuously for 12–24 hours at about 250 watts, keeping the whole house comfortable.
Just like with heating, you want to avoid cycling with air conditioning systems as well.

Can you recommend systems that work this way? Possibly also in combination with a mechanical ventilation with heat recovery system?

Uh – just a standard single-split air conditioning unit. Nothing special.

It has nothing to do with controlled residential ventilation.