Heat pump in historic farmhouse

Monika Friedlein has owned an old farmhouse dating back to 1939 in the Upper Franconian municipality of Mainleus since 2016. It houses a rented apartment and a small vacation apartment on around 140 m² of living space. The building was constructed using simple materials available in the region: Sandstone and locally fired bricks. “Nevertheless, it is a rock-solid house,” says the owner.

The previous owners had already renewed and insulated the roof, fitted simple interior insulation to the walls and installed plastic windows.

PREVIOUS HEATING SYSTEM IMPRACTICAL

Since 2008, the home had been heated by a water-burning stove, which brought heat directly into the living room, but also heated a buffer tank in the basement, to which the radiators in the other rooms were connected. The domestic hot water tank was also heated by the stove and, in summer, by a solar thermal system on the roof.

“The system worked well in principle, but has the disadvantage that you always have to add wood from morning to night. If you neglect this or are not at home, it gets very cold straight away. And that's obviously annoying if you have to work or want to travel.”

HEAT PUMP AS A FUTURE-PROOF SOLUTION

Together with heating engineer Christian Hörath, she looked for a solution that would make the whole thing more comfortable and future-proof and found what she was looking for at alpha innotec.

The new Hybrox 16 air/water heat pump delivers the heating output required for the building and easily copes with the high flow temperatures required for the radiators. Thanks to the tried-and-tested connection concept and the wide range of possible combinations, it was easy to integrate into the existing system and could be connected quickly and easily. The compact outdoor unit found a suitable location at the rear of the building.

The hydraulic module was chosen as the indoor unit, as its pre-installed components simplify installation while still offering many options for hydraulic integration. The prefabricated wall duct from alpha innotec was also used to speed up the installation.

NEW HEATING SYSTEM SIGNIFICANTLY MORE CONVENIENT

And this is what the new heating concept looks like: The wood-burning stove has been retained and can still be used for direct heating and to heat up the buffer storage tank for the radiators. Alternatively, the Hybrox heat pump can also charge the buffer tank and heat the house via the radiators. Hot water is heated exclusively by the Hybrox and the solar thermal system.

After the first few cold days, Monika Friedlein concludes: “It works very well, even without the wood-burning stove. The heat pump manages to heat all the radiators and keep the hot water at the right temperature, which wasn't the case before. Some of the rooms are even warmer than before.”

And the initial concerns about the noise level of the outdoor unit also proved to be unfounded: “I thought, well, it's going to be quite loud and I was a bit worried about that, also because of the neighbors. But to be honest, you can't hear it at all. Even directly in front of it, you can feel the draught, but the noise is minimal.”

And so the landlady is happy about a sensible and sustainable investment and her tenants are happy that they only have to heat with wood when they feel like it.