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Dont know the model but talking generally very close to the float will be a long screw.I've just installed a Grohe Rapid SL frame and cistern. The cistern water level sits too high. The instruction diagrams are awful. What exactly do I twist turn or pull to lower the water level?
Reply to the thread, titled "Grohe cistern water level" which is posted in UK Plumbers Forums on Electricians Forums.
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