Liquid filtering system, which comprises a vertical cylindrical outer casing comprising in turn a first base and a second base opposite to the first base, in whose interior are housed filtering elements, said liquid filtering system additionally comprising • a pipe that penetrates tangentially through the first base of the abovementioned outer cylindrical casing through which the liquid to be filtered enters,an interior collector pipe concentric to the outer casing with an outlet near the first base for the filtered liquid. • a removable watertight lid placed in the second base of the outer cylindrical casing, • a cylindrical package of slotted rings compressed by a spring, which is concentric to the interior collector pipe, • an omega-shaped piece adjacent to the second base that guides said spring and adapts to the exterior part of the interior collector pipe, leaving between both parts a chamber of variable volume, • and a set of holes drilled in the interior collector pipe with a fixed angle and location so that a cleaning reverse flow shot out through said holes hits the inside of the cylindrical package of slotted rings producing the spinning and separation of said rings, the liquid filtering system characterized in that it comprises • a flow adaptation piece which prolongs the pipe and that makes a gradual change from the circular section of the pipe to a rectangular section, that produces circular paths, for which reason the heavy particles descend and approach the periphery, by acting on them the forces of gravity and centrifuge, • a cylindrical mesh panel concentric to the interior collector pipe, and arranged between said interior collector pipe and the cylindrical outer casing, being the cylindrical package of slotted rings arranged between the interior collector pipe and the cylindrical mesh panel, - having a diameter smaller than the diameter of the interior collector pipe, - and located concentrically inside the interior collector pipe. • a pipe that penetrates tangentially through the first base of the abovementioned outer cylindrical casing through which the liquid to be filtered enters,an interior collector pipe concentric to the outer casing with an outlet near the first base for the filtered liquid. • a removable watertight lid placed in the second base of the outer cylindrical casing, • a cylindrical package of slotted rings compressed by a spring, which is concentric to the interior collector pipe, • an omega-shaped piece adjacent to the second base that guides said spring and adapts to the exterior part of the interior collector pipe, leaving between both parts a chamber of variable volume, • and a set of holes drilled in the interior collector pipe with a fixed angle and location so that a cleaning reverse flow shot out through said holes hits the inside of the cylindrical package of slotted rings producing the spinning and separation of said rings, the liquid filtering system characterized in that it comprises • a flow adaptation piece which prolongs the pipe and that makes a gradual change from the circular section of the pipe to a rectangular section, that produces circular paths, for which reason the heavy particles descend and approach the periphery, by acting on them the forces of gravity and centrifuge, • a cylindrical mesh panel concentric to the interior collector pipe, and arranged between said interior collector pipe and the cylindrical outer casing, being the cylindrical package of slotted rings arranged between the interior collector pipe and the cylindrical mesh panel, - having a diameter smaller than the diameter of the interior collector pipe, - and located concentrically inside the interior collector pipe. - having a diameter smaller than the diameter of the interior collector pipe, - and located concentrically inside the interior collector pipe.