Costs for the heating & sanitary trade

Circulation is certainly good, but the distances are never particularly long for me. ...

This is an important reason not to install circulation! Circulation is a real energy gobbler.
For short (and also medium) distances, I would definitely do without it.

Do I understand correctly that the towel radiators are connected to the HKV?

That almost looks like it, on the other side there are two electric heating rods listed, which actually speaks against it for me. But I definitely have to ask about that too...

Please note the advice regarding the necessary electrician. At first, it reads as if he delivers everything but cannot commission it because he is not allowed/willing/able to plug the connector into the socket.

How is the heat pump mounted, will it be hung on the facade? We are getting a concrete base where it will be screwed on. Our heating engineer is not at all in favor of mounting it on the facade.

The connection to the power supply is normally like that. It's high voltage after all. In my case, the electrician from the [GÜ] also does that. Yes, for the heat pump, the [GÜ] also makes the base plate for the outdoor unit, I have already discussed that with him. I would discuss the pedestal for the storage tank inside again to see if it is necessary. Actually, there shouldn't be that much vibration in the storage tank, right?

So, I had a very long and detailed conversation with the heating guy who made the last offer ( ). It was very enlightening. He shows himself to be very flexible in the various positions. - From his point of view, the circulation is not necessarily mandatory; he only included it because the TGA diagram provided for circulation. - A second outdoor faucet is unproblematic from his perspective, as long as I decide on that during the shell construction. - He can also supply and install sub-insulation or just supply it. He says it can basically be done well as DIY work, it's just tedious, but he will still make me an offer. - The buffer is a flow-through buffer and then sits in the return flow. It is supposed to prevent short operating times in throttled heating circuits, as the coolant also apparently lubricates the compressor and prevents too frequent cycling. He said even if I deactivate the ERR, it should be installed (because it should also work well with other people in a possible sale/rental) and with the hydraulics (directly in the return flow in front of the heat pump) it should not negatively affect efficiency. Can someone say something about whether this is true? Sounds somewhat plausible, but is it true? - Sanitary fixtures are optional, so the overall offer does not depend on whether I take them from him now or not - Like many others, he does not install third-party objects, which I also accept, as practically no one does it. - The wall radiator was a bit confusingly listed. Both are possible. Either into the heating circuit with a separate thermostat and heating cartridge, or just heating cartridge completely separated from the heat pump. - Wall heating is also possible, but it is elaborate, and due to the construction and necessary covering, at least 3cm or even 6cm are missing (depending on which wall surfaces one chooses) and then the available space can become tight again. The type of plaster must be clarified with the general contractor if everything goes smoothly... So far, all of this sounds pretty good. If I were to place the order now, he can also execute it at a suitable time. At least, that’s what he says.