Is the surcharge for an air-to-water heat pump justified compared to gas?

What is there to wait for? Do I also have to service my refrigerator? You can also clean the airways yourself and even my wife can check the filling level of the underfloor heating... The poor durability is certainly more related to poor hydraulics and system settings than to the performed maintenance. And if the creator of the botched system also takes care of the maintenance, it won't help either...

… and even my wife can check the fill level of the underfloor heating...

Now it's off-topic but do you live in the Middle Ages?

At a hefty surcharge. If I were a builder and knew for sure that heat pumps are the trend, I would also take gas as standard, fully aware that most don’t want it, and then charge a lot to sell heat pumps. That’s just how the market works.

That’s why I never wanted to build with a general contractor. Everything would have been way too opaque for me. We were also once at the beginning with general contractors, and all the surcharges they charged – when you googled it, none of it was comprehensible at all.

No, but my wife has nothing to do with technology and still has and can do it. I considered whether to write it like that, but wanted to provoke a little.

You wanted to provoke? I don't understand.

We built with GU and are very satisfied because the basic standard of our GU and our wishes were very close to each other. Therefore, the extra list was limited. That makes it affordable.