Combine heat pump and water-bearing fireplace

Under the above-described... the purely technical weakness of the air-to-water heat pump is indeed the deep winter, I can see that with my own. It consumes about 80% of its annual demand from December to February

That is the case with every heating system and has nothing to do with the air-to-water heat pump. As I said, even at minus 18 degrees a COP of 3. That is excellent and how often is it that cold anyway..

Well, with no other heating system is the "fuel" as expensive as with the heat pump. And not every air-to-water heat pump has a COP of 3 in practical operation for a long time. But I don't want to complain so loudly, since this afternoon the snow is off the photovoltaic... from 8 am tomorrow morning it will produce back

Well, with no other heating system is the "fuel" as expensive as with the heat pump. And not every air-to-water heat pump has a COP of 3 in practical operation. But I don't want to complain too loudly, since this afternoon the snow is off the photovoltaic... starting tomorrow morning at 8 am it will produce again

We have people here who achieve significantly higher COPs up to 5. A lot has happened in the last 10 years. But I also think gas is fine. A wood stove is a luxury like controlled residential ventilation. Not profitable but highly recommended.

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A wood-burning stove is a luxury like controlled residential ventilation.
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That is why I am glad to have a house with a double chimney flue. Setting up a wood-burning stove is easy there. If a house does not offer this option, it would be a disqualifying criterion for me (!) if I had the choice, should I face the decision again. In the past weeks, it has been burning almost around the clock in our home.

Is it possible? Yes!
Sensible? Yes, air machines of all kinds are crazy power guzzlers at subzero temperatures. That’s exactly when photovoltaics mostly don’t work either.
Technically feasible? Yes, but not every heating engineer masters it.
Affordable to implement? No!

Can you send me a private message? Unfortunately, I can’t do that...

Tell me more about your design. Flow temperature. Etc. :)

Sorry, I first need to clarify what is really included in the energy balance. The fireplace was NOT planned as part of the water circuit and can therefore be changed easily on my end. I have already arranged that. According to the architect, the additional costs for a water-bearing fireplace are about 8000 EUR; for that money, we will now install a larger photovoltaic system (+9kWp) on the roof. The economic efficiency is significantly better here.

The air-water heat pump is planned with a flow temperature of 35°C; heating is done via underfloor heating. The energy demand of the project is 21 kWh/(m2a) and the primary energy demand is 38, if that is of interest. What exactly do you want to know? :)

Regards