Thank you this is the screen shot of d.15. The plumber definitely mentioned pump speed - however, we do live in the Netherlands so maybe it was a translation issue.
Hello
we have a c15 year old Valliant eco boiler. A few of our radiators were not working and the plumber turned the pump speed up to 100%. Unfortunately the boiler is now too noisy and I would like to turn it back to Auto or 85%. I navigated to menu d.15 but pressing - or + are not...