Abstract: An apparatus for use in a liquid supply system having an inline liquid processor or purifier and which supplies liquid continuously or intermittently to an appliance or other point of use. The apparatus includes a valve structure which normally directs the flow of liquid through a pipe connected to the processor or purifier where impurities are removed before the liquid flows to the appliance and, when a predetermined quantity of liquid has passed through the valve structure, the flow of liquid to the processor is interrupted and the liquid is directed through a bypass pipe which is connected directly to the appliance.