Derived Three-phase questions

I can’t speak for the heat-pump, all I can do is help you insure that the IoTaWatt is correctly setup. As a first step, I usually try to get the mains reporting so that they are in close agreement with the utility meter. With derived reference, you should be able to get within a few percent of that.

So if you want to do that, you should start by reading the derived reference configuration documentation at Three-phase Power — IoTaWatt 02_03_20 documentation.

Then you might post a picture of your mains and a screenshot of your inputs display. My online time overlaps with Norway in your afternoon/evening, so if you get me in your afternoon and are prepared to go back and forth, we might be able to resolve the initial setup in a few days.