Abstract: The invention is a connection duct between the blower and a mixing device of a burner. The connection duct expands wedge-shaped along a first direction and diverts air from the blower to a second direction. The connection duct further comprises diverting means for diverting the air in a circular flow around the second direction corresponding to a longitudinal axis of the mixing device. The diverting means comprise a tube section with at least one inflow opening arranged in the peripheral wall of the diverting means. A truncated cone comprising a tapering section is arranged in the tube section so that the tapering section faces in the direction of the mixing device. A passage cross-section of the inflow opening can be adjusted by a tube arranged in the peripheral wall which can be rotated around the tube's longitudinal axis and bears against the internal surface of the tube section.

Abstract: The invention is a connection duct between the blower and a mixing device of a burner. The connection duct expands wedge-shaped along a first direction and diverts air from the blower to a second direction. The connection duct further comprises diverting means for diverting the air in a circular flow around the second direction corresponding to a longitudinal axis of the mixing device. The diverting means comprise a tube section with at least one inflow opening arranged in the peripheral wall of the diverting means. A truncated cone comprising a tapering section is arranged in the tube section so that the tapering section faces in the direction of the mixing device. A passage cross-section of the inflow opening can be adjusted by a tube arranged in the peripheral wall which can be rotated around the tube's longitudinal axis and bears against the internal surface of the tube section.