Turn the air purifier off. Unplug the power cord from the electrical outlet.
Lay the air purifier down on a flat surface with the front grille facing up.
Push in on the release buttons on the right and left sides of the grille. Pull the grille away from the unit to remove it.
Lift the old carbon HEPA filter out of the unit.
Set the new carbon HEPA filter into the unit where the old one was located.
Engage the tabs of the grille into the slots on the bottom of the air purifier. Swing the grille up and snap the top into place.
Turn the air purifier upright.