Air-to-air heat pump air conditioning? Comfort character?

I only understand half of your text.

You basically say that the photovoltaic system does not power the heat pump…

But in the last paragraph: That’s why, when building new. So you do say again to install an air-to-water heat pump?

Where is the catch?

Because whether air-to-air or air-to-water. A heat pump is still a heat pump and both need electricity (whether it comes from the photovoltaic system or from the socket doesn’t really matter at first)

Just read up on the functioning of an air heat pump and an air-to-water heat pump.

An air-to-air [Luft Luft] for example has heat recovery which, for example, a split air conditioner does not have.

The problem is many confuse the functions.

Try searching for both prefabricated house "face groups" Weberhaus, Schwörerhaus, Massa Haus, etc.

Certainly, like air-water heat pumps, it is a good solution, and yet there are reasons to do it differently without being less satisfied.
I had it before, but this time consciously did not, and I actually like our solution better; therefore, I would not want to spread it as the only recommendable solution.

Especially depending on the region, for comparable houses it is about double.
At the latest when winter breaks in on the Swabian Alb and the auxiliary heaters start running, the clock is ticking.

Given the high price difference in purchase and follow-up costs and sometimes also problems of both heating systems, I would not consider this as an absolute killer argument. The electricity meter runs with the heat pump as well.

As mentioned, there are already two here who also feel very comfortable with a different solution. As soon as someone wants a fireplace in the house and also likes to use it for their well-being, the question arises about the sense of an expensive underfloor heating with a heat pump. We absolutely wanted wide plank flooring in the house, and therefore the underfloor heating was out because that was important to us. We had underfloor heating before, which is also quite nice, but it also had its disadvantages.
For us, it is such that we also like the type of heat (fireplace) and then give up something else for it. Calculating or computing alone was out of the question for us; our individual comfort factor had the highest priority.
In short – here too, many roads lead to Rome.

And the fairy tale about the photovoltaics running the heat pump in winter is wishful thinking, which might work in the Rhine valley.

No one should have claimed that either, and we did not expect it.

If we are now only talking about air-to-air heat pumps (excluding split air conditioning units), I would like to point out the following small detail: An air-to-water heat pump is technology-open. Whether heat pumps are still in fashion in 20 years, whether we return to coal stoves, or put mini fusion reactors in our homes, the existing underfloor heating can be connected to the technology. An air-to-air heat pump almost forces you to stick with the technology.

Consumption databases of various heat pumps as a comparison benchmark can be found on Google. Certainly, every house is different, but this provides indications, especially regarding the important seasonal performance factor. (Air-to-air heat pumps and also exhaust air heat pumps perform rather poorly there for physical reasons. What the best solution for your own house is depends on your own planning and ideas.)

We also have an air-to-air heat pump.

Without Pce elements, the performance would be too weak.

Since we have a fireplace, everything is fine.

We have wood for free.
Chimney sweep about 45€ per year
Electricity consumption with domestic hot water heat pump January to 18.10. 1007 kWh

The air-to-air heat pump at least keeps the house dry and is off in summer.
(or turned on once a week / because of insects etc.)

Without Pce elements, the performance would be too weak.

What does that mean in plain language?

Since we have a fireplace, everything is fine.

That also works for us, although we have a climate split system which we sometimes use as heating in winter. We don’t have our own wood, but the consumption stays very moderate and ultimately the respective energy consumption surely depends more on user behavior than on the technology. For us, a fireplace was an absolute must. Our house is insulated to Kfw40 standard and it doesn’t get really cold inside at all, which was completely different in our previous "normal" house. Our domestic hot water pump works perfectly as well, although in hindsight even electric instantaneous water heaters would have been a good option for us.