Many modern WC systems are too small to accommodate a traditional ball float syphon flush mechanism. Instead the inlet valve is either a modified diaphragm type wit a very short float arm, and miniature float, or an ingenious vertical valve with a float cup that fits round the central column of the valve body. Ashford Plumbers have expert knowledge on this subject. Both are very quiet when they operate however the float cup will be slow to fill the cistern if it is fed from a storage tank rather than mains supply. In these slimline modern systems the old syphon flushing method is replaced by a plastic valve operated flush mechanism that is operated by top fitted button in the cistern lid. This also incorporates an overflow.The button is in two parts, depressing one part for a short low volume (small amount of water ) flush and both together for a full volume flush (large amount of water ).The button is linked to the plunger rather than the older style wire link float arm system. Installing.The valve design is very ingenious but can be very tricky to make adjustment for a correct fit so when installing the valve must be adjusted so that the critical level on the body of the valve is at least 25mm above the top of the overflow pipe. There is a threaded shank at the base of the valve assembly which gives the relevant adjustment so that correct positioning can be achieved. Guaranteed installation work for this equipment can be carried out by an Ashford Plumber .The float cup inlet valve consists of a rubber ring seal at the base of the cistern which will probably need to be replaced in time but with spares available should not cause too much trouble. It is recommended that you keep any documentation regarding the unit such as a diagram should you need to replace a defective seal at some point.