Power consumption of a heat pump

Superfund!

Take a look at
8.3 Thermal Disinfection

A start time is specified for thermal disinfection. When thermal disinfection starts, an attempt is immediately made to reach the set temperature. The selection of the hot water generators used for this depends on the operating mode of the heat pump system, the configurations, and the current states of the system. Thermal disinfection ends when the set temperature has been reached. To enable the thermal disinfection settings menu, a bivalent heating system and/or flange heating must be set to "Yes" in the pre-configuration.

... great meticulousness you are showing there. *thumbsup*

That could really be a cause.

I don't want to take credit for someone else's work here, found the PDF. I only searched with keywords and did a bit of reading myself. But after further searches, I don't believe this is the manual for operating the TE. Because the menu item with the night setback, which showed us, is not in the manual. Nevertheless, the thermal disinfection or Legionella program is an important clue as to what else it could be. So , search your manual for the function. If it also has a scheduler (which with a daily setting would be harmful to consumption), that could be the reason.

The heat pump heats the water to a maximum of 40°C, which is not sufficient for disinfection. The heating rod is limited to 55 °C. I have set a night setback as suggested. This actually resulted in a change in the curve. So my problem seems to be related to this after all. Since no night setback was set before, something is wrong with the control system. Now I am making an appointment with the heating engineer. He should reset the entire control system or replace it completely. Then there will finally be peace and unwanted power consumption will be prevented.

Thank you again very much for all the efforts to help me. I really appreciate it.

Merry Christmas and a Happy New Year 2024! Bernd

There is no menu item for the night setback, which showed us, in the manual.

Take a look at page DE-12 in the document. There is the night setback item there.
Since there are apparently several heating circuits, it could also be that the night shutdown is activated in HC 2 or 3. (Pages DE-13 and DE-14)

Ah! It is called only Absenkung not Nachtabsenkung. That's why I couldn't find it. Ok, apparently the control interprets this setting differently than expected. Good luck to , glad we could help and wish you happy holidays as well.