ᐅ Water-Bearing Fireplace or Wood Gasifier – Experiences?

Hello everyone,

After much consideration, we decided against a prefabricated house and chose a custom-designed home by an architect. A key reason was that almost all prefabricated houses rely on heat pumps, but we are not fans of this system (unfortunately, due to the house's orientation, installing a photovoltaic system is not practical for us).

Therefore, we would like to use a gas condensing boiler in combination with a wood gasification boiler or a water-bearing fireplace. We are now quite uncertain which option might be more cost-effective over time. We definitely want a wood stove in the living room...

The basic conditions are:
- New construction according to KFW 55
- Living area about 175 m² (1880 sq ft)
- Construction site in the Lüneburg district
- Own forest available (about 5 ha (12 acres)) mostly pine trees

Please do not start fundamental discussions like "Hey, heat pumps are still the best solution."
For us, the options mentioned above are the ones under consideration; we just want to know which would be more economical.

Has anyone had experience with these combinations?

Thanks and best regards

In any case, you will need a buffer tank to supply the underfloor heating through a mixing valve. When it comes to payback time, I am generally very skeptical. This might be more feasible with a wood gasifier boiler due to its higher efficiency.

Hello,

I have a combination of gas and wood gasification boiler.
There is a 2000 liter (530 gallon) buffer tank installed.
A fresh water station is used for domestic hot water.

The heated area is approximately 400 m² (4300 ft²) with underfloor heating.
However, there are also radiators connected through a separate circuit in the bathrooms, sauna, and hallway.

Chris2806 schrieb:
Hello everyone,

(...)

Definitely have the heating load calculation done, and then carefully consider what you can do with the 5-7 kW (kiloWatts) of air-side output from the stove in your living room when it’s burning strongly for hours...

In a modern house, the stove can easily deliver in 90 minutes as much power to one room as the entire house needs per day for heating and hot water...

Neither option is likely to pay off financially. You still pay just as much for space requirements, maintenance, and chimney inspections as you do for gas. And you still have to purchase the equipment.

So: it’s a luxury anyway, so build what you prefer and don’t try to make a cost-benefit analysis. That will only make you unhappy.

Just out of interest: where would the carburetor be located?

I kind of expected that...
The location of the carburetor would be the next issue then... Is it possible to install it without problems in the utility room? Or does it emit too much heat? The size of the room is about 16m² (170 sq ft), which should actually be sufficient.

Since we want a wood-burning stove anyway, we will probably opt for a water-heating wood stove.