What are the meanings of inlet and outlet?

1. Axial Fans

As shown in the following diagram, the side with the label attached is the outlet, and the opposite side is the inlet. The Fan can be installed with either side facing forward, but there is a greater chance of dust entering the Fan when the inlet side faces forward, which may necessitate a filter or other dust-preventive measure.

2. Box Fans

The inlet and outlet sides of Box Fans are specified for each model.

3. Examples of Inlet-and Outlet-side Fan Installation