ᐅ Which type of heating system is recommended for a KfW 55 energy-efficient house?

Lebensprojekt schrieb:
Yes, a ground source heat pump will definitely have lower energy consumption.
However, the additional investment cost of around 20,000 euros (about $22,000) is significant, and as I have learned, you have to expect high maintenance effort and related costs for the heat pump.

Regards

I don’t think the extra effort is really that high – you can get the complete system for that price. Also, I wonder what kind of maintenance you mean!?

Yes, I agree – but so far, most of what you hear about him is just hearsay.

And always using KfW standards as a reference – are you even aware that for KfW55, the calculations and therefore the costs are significantly more complex/higher?

Why do you think we chose KfW70 despite aiming for KfW55?

nordanney schrieb:
I don’t think the additional effort is really that high – for that price you already get the complete system. Also, I wonder what kind of maintenance you mean!?

I’m referring to the leak test, which is not required for closed systems, and possible adjustment costs that some companies charge to optimize the system settings.

Even with air-to-water heat pumps, reserves should be set aside for repairs, as these are highly technical systems that, for example, need to heat from -5°C (23°F) outdoors to 40°C (104°F) water temperature during winter.
These processes put a considerable strain on the pump. It should be clear that this cannot be without maintenance or consequences. The pumps are particularly vulnerable at the evaporator (air heat exchanger).
According to my heating installer (who installs heat pumps all day long), the material cost alone is about 1300 euros for the heat exchanger, which can fail after only 5 years.

Then you shouldn’t hire the heating engineer if they install such poor-quality equipment.

Again: There is no maintenance – do you also service your refrigerator?

And what kind of leak test? On the brine circuit? That is done by the drilling contractor and is part of the package... and every heating system needs to be adjusted.

How often does your freezer break down? It has to maintain a temperature of minus 18°C (0°F) even when it’s plus 30°C (86°F) outside.

And the gas condensing boiler actually involves combustion, so it definitely needs to be cleaned regularly to remove soot and other residues. In comparison, maintenance intervals for a heat pump tend to be longer.

A 6 kW ground-source heat pump costs around 10,000 euros plus the borehole.

With BAFA subsidies, a gas condensing boiler has a hard time competing.

BAFA funding is only available for existing properties.

With the developers I prefer, there is always an additional cost of 9,000–10,000 euros compared to a gas boiler. A ground source heat pump costs about 15,000 euros plus earthworks (laying collectors, etc.), so I easily reach 20,000 euros.
Ground drilling costs 5,000–6,000 euros per borehole.

Regards