A water purification apparatus for producing purified water, the water purification apparatus comprising: - a Reverse Osmosis device, RO-device, arranged to produce a purified water flow, the RO-device comprising a feed inlet arranged to receive feed water and a purified water outlet ; - a RO-pump arranged to pump feed water to the feed inlet ; - a recirculation path arranged to recirculate a proportion of the purified water flow from a first point downstream the RO-device to a second point upstream the RO-device , - a purified water path , arranged to transport purified water from the purified water outlet to a product water port , wherein the purified water path comprises a product water path arranged downstream the recirculation path to transport product water to the product water port , - a control device arranged to regulate a flow rate of the purified water in the recirculation path , - at least one detector arranged to detect at least one fluid property of the purified water in the purified water path , whereof at least one detector is arranged to detect at least one product fluid property of product water in the product water path including a flow sensor arranged to detect a flow rate of product water in the product water path , and - a control unit configured to control the control device to regulate the flow rate of the purified water in the recirculation path and to control the control device to control a product fluid property of the product water in the product water path in order to fulfil one or more predetermined criteria of the purified water in the purified water path , including that the flow rate of product water in the product water path corresponds to a predetermined flow rate, wherein the control is performed based on the at least one fluid property detected by the at least one detector including the flow rate detected by the flow sensor . - a Reverse Osmosis device, RO-device, arranged to produce a purified water flow, the RO-device comprising a feed inlet arranged to receive feed water and a purified water outlet ; - a RO-pump arranged to pump feed water to the feed inlet ; - a recirculation path arranged to recirculate a proportion of the purified water flow from a first point downstream the RO-device to a second point upstream the RO-device , - a purified water path , arranged to transport purified water from the purified water outlet to a product water port , wherein the purified water path comprises a product water path arranged downstream the recirculation path to transport product water to the product water port , - a control device arranged to regulate a flow rate of the purified water in the recirculation path , - at least one detector arranged to detect at least one fluid property of the purified water in the purified water path , whereof at least one detector is arranged to detect at least one product fluid property of product water in the product water path including a flow sensor arranged to detect a flow rate of product water in the product water path , and - a control unit configured to control the control device to regulate the flow rate of the purified water in the recirculation path and to control the control device to control a product fluid property of the product water in the product water path in order to fulfil one or more predetermined criteria of the purified water in the purified water path , including that the flow rate of product water in the product water path corresponds to a predetermined flow rate, wherein the control is performed based on the at least one fluid property detected by the at least one detector including the flow rate detected by the flow sensor . <EOS>