A storm door is necessary for providing insulation for the primary door in your home and can also be a decorative element as well. However, storm doors may not function properly after some time. Later model storm doors operate with a piston that closes the door, while older storm doors may close with a combination of a large spring and air. After continued use, the spring will lose its tension and the door may close too fast or slam shut. This could damage the door or you could be injured if you are unaware of this. It is possible to adjust the spring to get the door to shut properly once again.
Prop the door open with a heavy or large item. While you are doing this, examine how the spring operates. Find the inset screw that is located at one end of the piston and the other end is attached to the storm door.
Fit the blade of the screwdriver, depending on the type of screw head, you will either need a Phillips or slotted screwdriver, into the opening on the screw head.
Turn the screwdriver handle about one-half turn in a clockwise direction to move the screw. Move out of the way and remove the object propping the door and let it close by itself. If the door is still slamming shut, turn the screw one-quarter turn in a clockwise direction. Move out of the way and let the door close again. If it is still closing too quickly, turn the screw another one-quarter turn clockwise. Keep testing the door and continue adjusting the screw if necessary.
If you have turned the screw too far, then rotate the screw in a counter-clockwise direction. After testing the door and it is still closing too slowly, turn the screw in the opposite direction again. Continue doing this until you reach the desired door speed.