Bosch WFK 2801 trips mains RCD?

Bosch WFK 2801 trips mains RCD when on short wash cottons 40 deg c and possibly on other programs. Will not start unless water solenoids disconnected then runs sweetly even when solenoids reconnected until rinse when if pump/drum connector disconnected will proceed. Some times runs without a problem. Tryed everthing I know but without a manual (which I am not allowed) I am stuck. HELP! wHERE CAN i get a manual or some clues. Many thanks in anticipation.