Geothermal heat pump with controlled living space ventilation or without

There are two different main tasks (heat pump with geothermal energy and controlled residential ventilation) and technologies, which, when properly designed, are only minimally related directly to each other. Controlled residential ventilation is implemented to ensure a constant supply of "fresh" air and corresponding exchange without window ventilation in today's airtight houses, but above all also because of sweating/mold formation and the well-being factor of the occupants. However, the controlled residential ventilation should be equipped with heat recovery so that about 90% of the heat can be transferred back to the supply air. Trying to compensate for the cold air with a more efficient heating system is, in my opinion, the permanently ecologically and economically completely wrong way.

That's exactly the point. I am well aware that such behavior is not environmentally conscious. However, I would not classify this aspect under comfort. Let me try with another formulation: Are there other advantages of a ventilation system with heat recovery besides reclaiming heat, compared to a system without heat recovery?

By comfort, I did not mean the ecological aspect, but actually differences in comfort. That means, with a controlled residential ventilation system with heat recovery, you get fresh supply air significantly preheated blown into your house. With a pure ventilation system, you get the outside air supplied as it is outside. That means, at -5 degrees, the heating obviously has to work harder to bring the incoming cold outside air to room temperature. But the question is: Do you want -5 degree cold air blown in your neck when you are sitting on the sofa? Of course, the temperature is homogenized again by the heating, but a cold draft is a cold draft.

If you plan a controlled residential ventilation system, the additional heat recovery, viewed in isolation, probably pays off incredibly quickly. That means controlled residential ventilation always with heat recovery.

By comfort I did not mean the ecological aspect, but actually differences in comfort. That means, with a controlled residential ventilation system with heat recovery, you get fresh supply air clearly preheated blown into your house. With a pure ventilation system, you get the outside air supplied as it is outside. That means at -5 degrees, of course, the heating has to do more to bring the inflowing cold outside air to room temperature. But the question is: Do you want -5 degrees cold air blown in your neck when you are sitting on the sofa? Of course, the temperature is homogenized again by the heating, but a cold draft is a cold draft.

Are there actually controlled residential ventilation systems without heat recovery? I can't imagine that anyone still builds something like that, simple as it works.

Yes, there are plenty of them....this is then called decentralized ventilation system or exhaust system, etc.

It is also advertised in the glossy brochures and sold as the ultimate...window rebate ventilation is also a representative of the principle of ventilation without heat recovery.

That is not true, a decentralized ventilation system with heat recovery exists just the same. We have installed it (Lunos e2).

Decentralized simply means that the exhaust/supply air is exchanged at individual fans, and not centrally via a system in the basement/utility room.

You are right about exhaust air systems, there is no recovery there.