High-pressure radial ventilator for pressure-increasing conveyance of a compressible fluid with a spiral housing comprising an inlet opening for fluid intake and an outlet opening for fluid output, extending through a housing partition, and with a rotor that rotates around an axial rotational axis in the spiral housing and a blading made from multiple rotor blades, whereby the blading, when the rotor is rotating, induces an axial suction of the fluid through the inlet opening and a radially and/or tangentially diverted drainage of the fluid through the outlet opening and thus a pressure-increasing conveyance of the fluid from a suction side to a pressure side, and with a seal arrangement between the spiral housing and the rotor that serves to minimize pressure loss between the pressure side and the suction side, whereby the rotor comprises a cover pane via which the blading is axially covered on the front side, whereby the rotor comprises a seal surface, and whereby the seal surface is positioned on an intake ring on the cover pane such that the intake ring borders an intake opening of the rotor, whereby the seal arrangement comprises a contact seal arrangement in the area of the inlet opening, whereby the intake ring extends axially toward an outer side of the housing partition through the inlet opening, whereby the contact seal arrangement comprises the seal surface on the rotor and at least one seal element touching the seal surface, whereby the contact seal arrangement seals a ring gap between an edge of the inlet opening and the rotor, whereby the seal element is removably fastened on the outer side of the housing partition, whereby the contact seal arrangement comprises a seal housing with an installation space on the outer side of the housing partition where the at least one seal element is received, characterized in that the spiral housing comprises a suction nozzle opening up into the inlet opening that radially and axially overlaps with the seal housing, and that the suction nozzle comprises an internal nozzle segment via which the seal housing is shielded against the flow of the fluid being suctioned. whereby the blading, when the rotor is rotating, induces an axial suction of the fluid through the inlet opening and a radially and/or tangentially diverted drainage of the fluid through the outlet opening and thus a pressure-increasing conveyance of the fluid from a suction side to a pressure side, and with a seal arrangement between the spiral housing and the rotor that serves to minimize pressure loss between the pressure side and the suction side, whereby the rotor comprises a cover pane via which the blading is axially covered on the front side, whereby the rotor comprises a seal surface, and whereby the seal surface is positioned on an intake ring on the cover pane such that the intake ring borders an intake opening of the rotor, whereby the seal arrangement comprises a contact seal arrangement in the area of the inlet opening, whereby the intake ring extends axially toward an outer side of the housing partition through the inlet opening, whereby the contact seal arrangement comprises the seal surface on the rotor and at least one seal element touching the seal surface, whereby the contact seal arrangement seals a ring gap between an edge of the inlet opening and the rotor, whereby the seal element is removably fastened on the outer side of the housing partition, whereby the contact seal arrangement comprises a seal housing with an installation space on the outer side of the housing partition where the at least one seal element is received, characterized in that the spiral housing comprises a suction nozzle opening up into the inlet opening that radially and axially overlaps with the seal housing, and that the suction nozzle comprises an internal nozzle segment via which the seal housing is shielded against the flow of the fluid being suctioned.