I am also surprised why no one writes anything anymore.
But you also ignored a lot in that post, maybe that's why they lost interest.
Have you already insulated your pipes at the heat pump?
Have you gotten yourself an IR thermometer?
Well, I'll put it this way: if someone contradicts themselves from one post to the next in their statements and I ask why, and then get a snappy answer in return, I shoot back as well.
And if someone tells me something about optimization and thereby accepts a high consumption, then I can't take that as optimization seriously.
Basically, I have always tried everything that was written and also let it run for at least 48 hours.
Pipe insulation is ordered and will be delivered in the next few days. IR thermometer is available and has been tested. I can rule out a hydraulic short circuit. No return flow is nearly as warm as the supply flow in the heating circuit distributor.
Why Rastelli is ignoring me, I don't know.