<p>A valve (19) primarily designed as a float valve to control the flow of water under pressure into a cistern has an upstream chamber (22) and a downstream chamber (23). The upstream chamber (22) communicates an inlet (21) for mains water supply with outlets (17, 17A) and the downstream chamber (23) has an outlet (24) which is closed by a valve (25) when a float rises a float rod (14). A primary valve member assembly comprises a piston (3) to the downstream end of which a diaphgram (5) is attached. When the secondary valve (25) is closed pressure on diaphragm (5) causes piston (3) to close the inlet (21). When the secondary valve (25) is opened by the rising float the piston (3) is expelled from the inlet (21) allowing water to flow into the cistern through the upstream chamber (22).</p>
