The matter with heating - air/air, air/water, or gas?

I meant the regulation at night. You actually want it cooler then.

Possible with radiators, not with underfloor heating... widespread misconception that regulation is necessary... because usually people come from an apartment or a house with radiators and "don't know it any other way"... but there are already plenty of threads about that... so back to the topic...

I stick to the fact that gazing into a crystal ball and fiddling with fictitious energy prices ultimately brings nothing. As I said, it’s just a few euros per month, the previously mentioned 80 euros I cannot understand when comparing modern heating systems in new buildings.

In other words, economically speaking, it doesn’t matter much whether gas, pellets, or heat pump. You can calculate everything to confirm your own opinion. As long as the system is properly planned and executed, it doesn’t matter either, because the differences in heating costs are marginal.

So sit back and look at the requirements of the house. And then choose the appropriate system accordingly.

By the way, optimizing can become a time-consuming hobby, which I indulge in from time to time. But you always have to put it into perspective ;-).

Air-to-air heat pump is not necessarily an uneconomic alternative in the right system... you shift parts of the investment costs to later. Even a pure electric heating is not ruinous at 6000 kWh heating demand...

We were at the energy consulting center last week. Unfortunately, it was a waste of time... the "consultant" didn't even know what an air-to-water heat pump is at first and instead spent 20 minutes clicking around the KFW site :(

I have seen/read/heard several times now that you should know the primary energy demand of the house, or that a heat load calculation should be done. Should you get this data from the providers (also before signing)? Or can you somehow find out or calculate it yourself?

Thanks!

Heat load calculation can be simplified and done by yourself - it should be done for each room... even better: your heating installer should do it, who can - with some luck - do it much better. Primary energy demand - at least theoretically - we were able to find in our Energy Saving Ordinance documents. However, primary energy demand is actually only relevant for KFW calculations and of course for the Energy Saving Ordinance - what you actually pay for can sometimes be different. You need heat load calculation to choose your heating system (since these are always only available in 2 kW increments, an estimate is usually sufficient) and for the design of your underfloor heating - that is, for determining the spacing of the pipes.