Headquartered in Pella, Iowa, the Pella Corporation manufactures and installs doors and windows for new constructions and remodels. That includes Pella's selection of sliding patio doors. If the Pella sliding door does not lock tightly onto the strike plate on the edge of the door frame, it creates an avenue for drafts to enter the room, and for room air to be lost to the outside. Focus on the door latch, which secures and locks the door to the frame, to repair the problem.
Open the Pella sliding door enough so that you have room to stand and work between the door edge and the door frame.
Flip the lock lever on the side of the door down, so that it extends the door latch out of the door.
Twist the adjusting screw located on the door edge, directly above the door latch, counterclockwise, using a flat-head screwdriver. You will notice the latch moving in closer to the door edge.
Shut the door and lock it. Pull back on the door handle, to make sure there is not too much play between the door and the frame.