Yes - Cyl seems to heat up fine - all 22mm between boiler and cyl, predictably...If the boiler is at 26% output then only running at 4.94kw and a flowrate of 3.37LPM!! If that is correct then something seriously amiss. Is the DHW cylinder heat up time OK.
It's got sludge removing stuff in the system at the moment, which is still building up on the filter magnet to maybe 2 - 3 mm thick bumps in a day or 2, - I'm hoping this starts to clear more out now the flow is going round the rads instead of the bypass loop stupidity...
Before the boiler change, I had a grundfos pump set at maximum rate and that did heat up the rads OK (old glowworm 18HXi, looked ready to die at any moment)
Th new Vitodens has a more powerful pump internally - but the boiler never seems to set it above 65% speed, making it less powerful than my old one - and there's no minimum speed setting option, only a max speed setting for the pump, which I had already set to 100% before I found the bypass loops... The boiler pump is a fancy PWM controlled version, so no switch or buttons to play with, unfortunately.
I was wondering about getting the old pump put back in place...