: I have something like this, and it fits perfectly into the category "what I treated myself to." It only makes sense to a limited extent because you will never recoup the investment financially. We have it this way because: - my wife and I want the fireplace - I like the concept - only air-to-water heat pump is possible here, the only brand offered by the general contractor suitable for a 3-4 person household. We are 5 people with 3 girls (topic hot water) - firewood costs us almost nothing here in the village Now to the technical part: We have a set fireplace boiler from the stove maker in a 60 sqm room with an open stairwell to the attic. The boiler nominally has double the heat output the house needs, but it releases 80-90% of the heat not into the room. Normal stoves with water jackets are either too small to efficiently make hot water or overheat the room in today’s low-energy houses. The effort for a large buffer, hydraulically separated system, control, piping, planning exceeds the financial benefits of such a system, unless you heat exclusively with it. Since we operate it in parallel with a heat pump, the effort was enormous. We have the luxury version of the control: Brunner BHZ 3.0 with buffer: costs almost 10,000€ alone. Set fireplace boiler: 10,000€ without frills like wood compartment, stove bench, or the like. Heat pump 7,000€. All gross including installation. Planning, coordination of trades, electrical installation: own work and very, very elaborate, since no one here delivers the combination from a single source. And the luck that the general contractor cooperated and gave me free rein with the trades. Would I do it again? I don’t know. The atmosphere, the feel-good factor at the fireplace, the satisfied play instinct (I can measure the entire system via heat meters and remotely control it over the internal home network) are already a gain for me. My wife enjoys the wood fire and that we are not dependent on a single energy source. The goal is to operate the whole system via the photovoltaic system in 1 or 2 years. That’s not yet installed on the roof. My tip: If you are not an installer or don’t find one who delivers everything from a single source, don’t do it. Many stove dealers here would have sold us everything. Living room with sauna effect included.