I just thought I will given an update on following the suggestions given here.
I have tried setting a constant temp of 20deg in schedules at it has worked very well in terms of comfort. We are having a mild warm weather but chilly mornings and this is definitely good advice . Have to still see how the power consumption is in really cold days <5 degrees.
I also noticed that the flow temperatures and power usage spike whenever the temperature drops below 20… usually overnight. The pump runs fast to about 40-45 degrees warms up to 20 and switches off. I presume this is bad for COP (no measurements).
Since then I have switched to fixed flow temperatures and have been slowly lowering it to flatten out the heat pump usage spike and see how long it takes to regain any heat loss.
Currently running at 35c with a modulation of 5 in Delta T settings. Is there any point in trying to go any lower. I understand that the Daikin ones don’t like going any lower. Is that correct? Did anyone manage to go lower with their heat pumps. Did doing any radiator upgrades help with that?