While you wait for answers, we may have found some information which could help you.
Click here for Grohe Concealed CisternSlow fill of toilet cistern?
Grohe 42181 toilet filler valve leaking?
Short burst of water entering cistern ?
The push button on my Grohe Adagio stopped flushing ?
Grohe seals 14.11.30 4 DAL?
Replacement of bellows in Grohe air button?