Old building with room ventilation and "cooling"?

Hello everyone,

next year I will "take over" my parents' old building.

- Year of construction early 1900s, 2 full floors, 160mm relevant living area
- Insulation, windows, etc. from early 2000s
- Sanitary, electrical from 1981
- Currently liquid gas for heating and water, but that should go (above-ground tank --> space)

Since we will renew all walls and floors anyway, we would also like to install a central residential ventilation system, including air conditioning.

Now I have read here several times that heat pumps with passive cooling bring hardly any benefit.

My idea now was:
- Heat pump for hot water and heating
- Central residential ventilation in all rooms (pipes in walls/ceilings)
- Central air conditioning that can significantly cool via the same residential ventilation
- Supported by photovoltaics or solar thermal (flat roof garage with 50mm, perfectly oriented)

One can argue about the cooling, but for health reasons it is simply necessary.

- Is this sensibly implementable and are there ready-made systems?
- Photovoltaics or solar thermal, which is more suitable for this setup?

Thanks for your help,
best regards Rüdiger

Is there already underfloor heating or should it be newly installed? Otherwise, I am not sure if a heat pump makes sense. Did I understand correctly that a controlled residential ventilation (Kontrollierte-Wohnraumlüftung) is to be installed? Unfortunately, you cannot cool with it; the air conditioning system would have to be installed separately.

Hi,

There is no underfloor heating.

Unfortunately, you cannot cool with that; the air conditioning would have to be installed separately.

The question is: Can that be combined with the pipes? Or do I really need, depending on the room, 1 x controlled residential ventilation supply air, 1 x controlled residential ventilation exhaust air, and 1 x air conditioning?

... Did I understand correctly that a controlled residential ventilation system (Kontrollierte-Wohnraumlüftung) is to be installed? You cannot (unfortunately) cool with this, the air conditioning system would have to be installed separately.

That is not (generally) correct. Post-cooling coils in the controlled residential ventilation system enable cooling. However, with all the possible difficulties to consider (condensate ...) My nephew is currently building it like this (Helios), I can gladly report in a few weeks how it turned out. AN air-to-air heat pump is inefficient with PC (passive cooling), a brine-water heat pump is more suitable. Both probably only make sense with surface heating systems since only there low flow temperatures are possible. Combination of "normal" radiators and solar thermal (both "high-temperature technology") or heat pump and underfloor heating or concrete core activation.

Hi, There is no underfloor heating. The question is: Can this be combined with the pipes? Or do I really need 1 x controlled residential ventilation supply air, 1 x controlled residential ventilation exhaust air, and 1 x air conditioning per room?

Exhaust air goes to the bathroom and (living) kitchen, supply air to the living room (or 2x living kitchen depending on size) and to all other rooms. This is calculated by the heating engineer or, for the heating engineer, by the manufacturer of the controlled residential ventilation.

In controlled residential ventilation, areas with overflow are normally used. has already described this. That means there is not supply and exhaust air in every room.

If you want to cool, additionally use an air conditioning system. You don’t need it in all rooms either.

Cooling via the controlled residential ventilation (not with controlled residential ventilation!) is possible but complicated and not so easy to control. The variant described by is still an “emergency solution” (but a good one). The air exchange would have to be significantly higher (5-10 times per hour) and a proper air conditioning unit should be placed before it. It also makes sense then to work without overflow areas (otherwise no different temperature zones). We have a similar system.

For you, a more effective variant is rather classic controlled residential ventilation + central air conditioning system with connected room units (e.g. bedroom and living room).