I've only fitted two, they've bith gone wrong. One gas valve the other hw flow switch. The pressure vessel set up is very poor, its an after thought because they use remote ones in Holland. Or where ever they come from.
The built in Timers a poo electronic one, that a seventy year olds got no chance with. There's no option for a timer like the vaillant 150, which is dummy proof. The whole user friendliness of it is absolute rubbish tbh.
Gold pump instead of grundfoss as well. One less moving part maybe, but the ones that do break.
can you tell I'm not that impressed?