I am another homeowner who has inherited a Dudley Niagara dual flush system that no longer works as it should - I hope someone here can advise me on how to proceed.
I have a concealed cistern in a built-in vanity unit with an air-operated dual flush valve. The main valve assembly was replaced...
I watched seven videos and read numerous instructions and none tell me what I need to know. Have removed both metal push buttons to reveal a central retaining screw between the two plungers which the buttons operate. All the instructions say to unscrew this screw to allow the lid to be removed...
