Instructions on reversing the airflow direction in Filterfans for PF 11000 - PF 43000 series
Material Needed: Phillips Screwdriver
1. Remove the (4) screws on back surface of the fan (see image below for example)
2. Physically flip the fan over 180°
3. Reinstall the (4) screws to hand tightness.
Filterfan Model PF 65000 - 67000 Including Slim Line Fans:
Material Needed: Thin wedge, shim, or scrap material to prevent tab from closing while moving around the fan
1. Starting at the bottom left tab of the fan, push down to release the tab 
2. Once the first tab is open, use a type of thin wedge, shim, or any type of scrap material and place it between the fan and the housing of the fan. Release both bottom tabs first and place your wedge or shim underneath them.
3. Once all four tabs are released, physical flip the fan unit 180° and snap back into position starting with the bottom edge first.
