An inline fan is a type of ventilation fan that is installed within the ductwork of a ventilation system rather than in the room from which it extracts air. These fans are designed to move air efficiently through long duct runs, making them particularly effective in applications where additional extraction power is required, such as above bathrooms or kitchens.
Inline fans are typically used in situations where the extraction of air needs to occur from a distance, such as from a bathroom or kitchen to the outside of the building. They operate by pulling air through ducting that leads from the source of moisture or pollutants to an external grille. This design allows for a more discreet installation compared to wall-mounted fans, which can be visually intrusive.
Inline fans usually feature a centrifugal impeller, which enables them to generate high airflow rates even over long distances. This makes them ideal for applications where the ducting must navigate around structural obstacles or when the extraction point is far from the external wall.
In a typical UK home, an inline fan might be installed in the loft space above a bathroom. The fan extracts humid air through ducting that runs from the bathroom ceiling grille to the outside wall. This not only helps to prevent damp issues but also maintains the aesthetics of the bathroom by keeping the fan hidden from view.