House planning final: heating components, what makes sense - no air heat pump

Hello everyone,

after spending the last few weeks figuring out what, how, with whom and how big we want to build, it is now about what I consider almost the most important: choosing the right technology, especially heating and cooling technology. We are planning a 144 sqm house according to Kfw 40 standard. Not basemented, low-lying area NRW, 4 people.

Our general contractor/general planner installs the following standard components:

- Nibe air heat pump Fighter 755 G (variant of 750) in combination with solar module with 2 KWp output.
- Underfloor heating on ground and upper floor
- 180 liters of domestic hot water

There is an optional possibility to install the following components at an extra cost:
- Expansion of the photovoltaic system to 3.3 KWp
- 7.0 kWh home battery
- Inverter.

The inquiry regarding heating capacity and expected electricity consumption led to rather unsatisfactory results. Or to put it clearly: too much marketing blah blah, too few answers that dispel my concerns, which are:

- Is the Nibe 755G with the small solar module dimensioned large enough despite insulation to handle the 144 sqm without constant additional heating? Are 180 liters especially with two small children not clearly too little? And does a five-figure cost extension for a larger photovoltaic module with battery even make sense in relation to the price?
- Is an optional stove worth it at all? At 7,000 EUR for the fireplace plus the stove itself, I don’t see any economic benefit. We are almost dropping it.
- What other “combinations” besides air heat pumps would you consider?

Basically, I am not opposed to the air heat pump, but if a forecasted demand of 6000 kWh per year for hot water and heating is the standard of this combination, then I achieve this in the current 1990 house with poor insulation and gas boiler at a similar cost. You can guess which general contractor it is. Replacing the standard components is not so easy.

I am about to hand this topic over to a heating expert because I really don’t trust the general contractor on this point and they don’t do much more than order their standard supplier to install the standard stuff. Therefore, I am of course very grateful for expert tips in advance on this topic.

Best regards

Options are not worth it - neither battery nor oven. Money is cheap, ovens are cozy; if you want to have one, why not. By the way, photovoltaics have no impact on heating performance. Ask your GÜ for a heat load calculation. This should roughly correspond to the output of your heating system. The DIN unit is kW.

Moin Moin

Regarding the exhaust air heat pumps, including the 750 series, something was recently written in the area of "Lüftungsanlagen / Wärmerückgewinnung".
However, the supporter of the systems did not respond anymore.

I consider these systems to be complete rubbish.


Olli

I am with and . A fireplace and stove are only worth it for coziness. Do you have a photovoltaic or solar system on the roof? In combination with a heat pump, I would tend to favor photovoltaic. But whether it pays off is often doubted. The design of your heating system must be done based on the heating load calculation. No one here in the forum can answer that generally for you.

Thank you for the feedback.

Yes, I had read the thread, but apart from wild arguments, there was little constructive discussion. I had difficulty, in any case, objectively identifying the pros and cons.

Sorry, I of course meant a photovoltaic system. The combination would be a Nibe 750 with [Photovoltaik Anlage] or optionally a larger [Photovoltaik-Anlage], inverter and battery. However, you first have to recoup the 12,000 EUR. If you want to do without fossil fuels like oil and gas and are already working towards KfW 40 in terms of insulation, besides the exhaust air heat pump, are there other options that definitely should be included in the consideration?

Besides the auxiliary heating in those things, especially in winter, I also have possible concerns about drafts and similar issues. Overall, you hear a lot of negative things and the trend here seems to be heading in a similar direction.

Photovoltaic system or alternatively a larger photovoltaic system, inverter and battery. The 12,000 EUR must

For 3.3 kWp? Rhineland greetings