Abstract: Method for purification of a liquid, which method comprises the steps of; conducting the liquid through a purifying chamber (19), activating a UV light source (22) comprising a gas for lighting and illuminating the liquid in the chamber by the UV-light source. In order to increase the efficiency and shortening the start-up time of the UV light source, the gas is heated to an increased temperature prior to activating the UV light source for lighting, using a heating element which is placed outside the WV light source.

Abstract: System for supply of liquid comprising a discharge point (15), a liquid line (5, 5, 12, 16, 18) connecting the discharge point to a flow regulator (2, 41), which in an active mode supplies liquid from a source (1, 40), through the liquid line to the discharge point and which in an inactive mode prevents liquid flow through the line; and a liquid purifier (6), which is connected to the fluid line, between the discharge point and the flow regulator and which comprises a UV-light source (10). For achieving reliable automatic activation of the UV light source upon activation of the flow regulator, the flow regulator is electrically controlled and means are provided for detecting a supply current to the flow regulator and in response thereto activate the UV-light source.

Abstract: The present invention is for method and means for purification of water using reversed osmosis. Water is forced through a membrane element (10) under pressure, which is obtained by a high pressure pump (2), where the water which is supplied to the element (10) is both from the outside supplied, unpurified water and internally circulated water that has passed by the element at its inlet side. The high pressure pump operates intermittently and the quantity of water that is circulated internally is at least as large as the quantity of water that is supplied from the outside. After that the pressure has been reduced there is a time delayed flush cleaning of the element (10) by flushing with water that is supplied from outside.