While door closers have varying designs, adjusting its closing and swing speed usually involves locating the adjustment screw and turning it clockwise or counterclockwise to a preferred tension and closing swing speed. The swing speed and tension of door closers are controlled by dampers that either have pneumatic or hydraulic mechanisms.
The following shows the basic steps in adjusting a door closer:
Examine the door closer
Since most types of closers are located near the top of the door, use a step ladder when examining the door. Make sure that the ladder is stable enough to ensure safety.
Locate the adjustment screw
In the case of storm door closers, the adjustment screws are located near the attachment for the door bracket. In other types of closers, the adjustment screws may be labeled "Latching Speed," "Swing Speed" and "Back Check." If the adjustment screws are not labeled, a simple trial and error approach will help determine the right adjustment screw.
Make the adjustment
The screws may be adjusted using either a screwdriver or a small wrench. Make adjustments by turning the screws either clockwise or counterclockwise in minute increments. Test the door for the effect of the adjustment. Continue making adjustments until the preferred door tension, swing speed and closing speed is achieved.