I have 2 tips.
The first is to set all thermostats on maximum and then adjust the kurve and tuning (red and gray wheel) so it controls the heat inside from the heat pump.
It is better for the pump if no thermostat is open/closed over time, that can trigger immersion heater unnecessarily.
You ca have a few thermostats active in the rooms that you want to have a little cooler but the most should be always open.
Then buy a room temperature control to the pump (RG10).
It will detect when you put on a fire and will reduce the supply temperature from the heat pump.