While you wait for answers, we may have found some information which could help you.
Click here for Dual Button Flushinghow do I change the bellows in the push button unit for the grohe cistern?
Grohe 42181 toilet filler valve leaking?
Short burst of water entering cistern ?
how to take unit apart?
Have I been charged way to much for having a loo mended?
grohe toilet cistern leasks ?