Hi Judyyy
The thing with the buffer is not quite right. The underfloor heating can serve as a buffer to some extent.
The stove operates with a return temperature of at least 55°C, the underfloor heating with 25°C. This cannot be reasonably combined as is. -> Buffer Then also use this, for example, as a hygienic storage tank for solar domestic water heating.
From personal experience
New build 1999 4 people normal hot water demand Washing machines connected to cold water
Pellet stove 800 ltr hygienic storage tank 10m2 flat collector
New build 2015 3 people high hot water demand Washing machines connected to hot water
Pellet stove 1500 ltr hygienic storage tank 25m2 vacuum tubes
various similarly configured customer systems.
If you can basically get used to a pellet stove in the living room and the associated noise level, there is actually nothing standing in the way.
Olli