Which heat pump? Ventilation system / Air-to-water heat pump

An exhaust air heat pump does not either.

An exhaust air heat pump can never compensate for the loss of 6kW.... At least not according to my understanding of the system.

I do like the pink forum, but this constant recitation of the same things is quite annoying.
- Everything except passive house standard is rubbish, no matter how uneconomical it may be....
- Trench collector is the only true form of energy generation, and the price is always nicely compared between trench self-construction and everything else completely by professional company, disadvantages are completely ignored or talked away ...
On the topic: No exhaust air heat pump, totally my opinion. Whether geothermal or air-water heat pump is a question of economic viability and strongly depends on the offers for the systems and various other conditions. There is neither good nor bad here, the individual case must be considered.

By the way, you can plant on the plots above without any problems. Or do you all avoid planting a tree because the drinking water pipe goes into the house at that spot? (It is made of the same material as the brine pipes and lasts forever).

Our heating runs via surface collectors in the garden. We were specifically advised not to plant anything deep-rooted above them. Especially in spring, you can also notice from the vegetation and the snowmelt that the soil is somewhat colder. Advantage: mowing the lawn only starts 14 days later.

I wouldn't want to blow 6kw through hot air..

You don't do that either? The exhaust air heat pump also heats through underfloor heating

On the subject: No exhaust air heat pump, totally my opinion.

Yes, but WHY?

Alright, often these are also air-to-air heat pumps. But even if the heat pump is supposed to bring the heat into the water, just think about it: if you need 6kW of heat, where does it come from? From your exhaust air? If the exhaust air heat pump only operates with a COP of 2, then it needs 3kW of heat from the exhaust air. Unfortunately, the heat capacity of air is very poor, so it has to suck in a lot of exhaust air. How is this replaced? By fresh, cold air from outside. This must also be heated with the help of the heating system so that it does not get cold inside. For this, more exhaust air is needed, and so on. The exhaust air heat pump is thus eventually working to produce enough warm air for itself so that it can even operate. At a certain outdoor temperature/required output, this simply collapses, and you basically only heat directly with electricity.