Things You'll Need
Pella manufactures two types of patio doors in hinged and sliding varieties, as well as main entry doors and storm doors, many of which are fitted with locks. Over time, the moving parts of the lock can seize, preventing the door from opening. With a little maintenance, you should be able to release the sticky lock and prevent it from jamming again in future.
Spray a little graphite powder into the keyhole or any other part of the mechanism, and work it around by inserting the key or moving the lock lever. Graphite powder is used by locksmiths to loosen stuck parts.
Spray water-dispersing spray into the lock, if you suspect the parts may have rusted together. This is usually the case if the lock sticks on its first use after the winter. Avoid overusing water-dispersing spray, as it tends to attract dirt. Usually a little is enough to loosen the mechanism and release the lock.
Once the mechanism has been released, adjust stiff Pella sliding door locks by loosening the screws holding the latching strikes on the inside of the door frame. Pry off the plastic covers, loosen the screws, and slide the strikes up or down a few millimeters. The door might be difficult to latch and release if the strikes are misaligned. Turn the screw on the inside of the door near the ground to raise or lower the door's rollers.