Abstract: The present invention consists of an apparatus and method for supplying purified water to a faucet or other apparatus for use from a purification loop maintaining water in constant motion. The apparatus allows the user to select and withdraw the amount of water needed in a closely controlled fashion while any unused water remains in the loop where it is continually purified. A control valve with a manually rotatable spool permits the purified water to be adjustably tapped or withdrawn for various end uses.