Bissell Internal Air Duct Koblentz It is the knob you

It is the knob you turn to set the brush height for different carpet pile depths

A cracked or warped bottom plate allows air to leak into this chamber from the sides

so switching from rug to bare floor takes only a moment

The metal lining is built for cool to warm ash pickup and is not intended for hot ash or live coals

or laminate

Bissell Internal Air Duct Koblentz It is the knob youThis genuine OEM internal air duct fits the Bissell 1383 and related deep cleaners, routing airflow through the machine. It maintains the internal path that carries air where the design intends. A cracked or broken duct leaks air and disrupts the intended flow, which can undercut cleaning performance and stress nearby components. A precise replacement restores the sealed internal path and proper function. Fits: Bissell 1383, 66Q4, 66Q42, 73A5, 8920,