We recommend that you keep the outlet or intake at least 100 mm away from the wall.
The following is actual measurement data that measures the effect of the distance between the fan and the wall on maximum airflow.
Five types of propeller fans with different characteristics and sizes were used to measure the data. When the distance to the wall was about 100 mm, the "percentage of maximum airflow at no load" for all fans was 100%, indicating that the wall had no effect.
