The flaps of the new Filter Fan Plus series are inspired by the plastic louvered shutters used for instance in households for the evacuation of exhaust air (kitchen, bathroom, dryer, etc.). But then again, they are significantly different.
Our engineers put a lot of thought into the form of the air-flaps: e.g. the flaps are not flat, but have an optimized curve, enabling them to react to small airflow volumes with the maximum opening of the flaps. Thereby the air resistance is positively affected by the air-flap technology.
STEGO even went a step further when combining the flaps with a fan, and adapted the sizes of the flaps to the ideal operating point of the fans (each fan has its own individual spiral-shaped air turbulence pattern). This ensures an optimized airflow for any filter fan size.