Heat pump is not compatible with a water-bearing fireplace

Then there must still be a calculation of the primary energy demand etc. in the house documents.

No, it wasn't done either, at least we have nothing. Because someone wanted that before.

do you think the chimney connection is better like this? Or the old version? In the old version, we had the problem in winter that the temperature in the buffer did not rise, but it was barely bearable in the living room. That's why we wanted this modification.

Phew, good question, I know much more about heat pumps than about fireplaces. I'm not a big fan of it either. Today we were also annoyed by the neighbors who filled everything here with smoke... Basically, I think the connection was better before than now. But the real question is, as Mycraft already said, how the underfloor heating is connected. And above all, did you have all the room controllers set to 1 there? You should be aware that as soon as the temperature on those is exceeded, they completely close the flow. So that's not regulation but an on/off. How then is the heat from the fireplace supposed to be transported to other rooms? The energy performance certificate has been mandatory since 2002, hasn't it?!

Puh, good question, I know a lot more about heat pumps than about fireplaces. I'm not a big fan of them either. Today we were also annoyed by the neighbors who smoked everything up here... Basically, I think the connection was better before than it is now. But the real question, as Mycraft already said, is how the underfloor heating is connected. And above all, did you also have all the room controllers set to 1? You should be aware that as soon as the temperature on those is exceeded, they completely shut off the flow. So that is not regulation but an on/off. How is the heat from the fireplace supposed to be transported to other rooms then? The energy certificate has been mandatory since 2002, hasn't it?!

Yes, we already had it set like that then. And back then it was said that the underfloor heating would consume all the heat, which is why nothing reached the buffer. But since it was unbearably hot here, we insisted on the renovation now. And behold, it works. Here in the living room it is bearable and the energy reaches the buffer. What is the energy certificate supposed to be mandatory for?

Yes, we already had it like that there as well. And back then it was said that the underfloor heating would consume all the heat, which is why nothing would reach the buffer. But since it was unbearably hot here, we insisted on the conversion. And behold, it works. Here in the living room it is bearable and the energy reaches the buffer.

Just because it flows through other pipes in the same storage, it is supposed to reach with one variant and not with the other? Sounds physically illogical at first. It might take a bit longer, but the fact that it supposedly didn’t work at all with one must have been due to something else. Valve not open or something.

What is the energy certificate supposed to be mandatory for?

For residential buildings.

Just because it flows through other pipes in the same storage tank, it should arrive in one variant and not in the other? Physically, that doesn’t make sense at first. It’s possible that it takes a little longer, but the fact that it supposedly doesn’t work at all in one case must be due to something else. Valve not open or something like that. For residential buildings.

I understood it so that the old variant flows in a closed circuit and the new variant arrives in the large open water. No idea. We certainly don’t have anything like that and haven’t needed it so far.

Just because it flows through other pipes in the same storage tank, should it arrive in one version but not in the other?
Physically, that doesn't seem logical at first.

Previously, the wood stove was connected in such a way that it only warmed the lower part of the storage tank, and stratification may have occurred. Now it is connected so that the entire storage tank is flowed through, and thus more heat can be transferred to the contents.