So every time the storm door is opened it slams shut instead of gently closing like it used to? What you may not have noticed is that this all started back when you took out the screen panels you use in summer and put in the storm-door windows you use in winter? It’s simple enough but often overlooked. Glass weighs a lot more than screen and that extra weight causes the door to slam shut unless you tune it up a little. That pneumatic tube near the top is called the “door closer” and on its end is a small screw. Turn the screw clockwise and your door will close slower…so it won’t slam shut. Then next spring, when it’s time for screens again, turn it counterclockwise to re-adjust for the weight.