If your patio door is difficult to open and close it may require adjusting or a new set of wheels. Try adjusting the patio door before spending any money on new wheels.
Adjusting the Wheels
The patio wheel adjusting screws are located at either end of the bottom section of the door. Some patio doors have a blanking plug covering the adjustment hole, remove the plug and use a torch to shine into the bottom section of the door to determine where the screw is located and what type of screw it is. There maybe two screws that are visible, one is an adjustment screw and the other is a fixing screw that holds the patio frame together. Use a long screwdriver to turn the adjusting screw in a clockwise direction to raise the patio. Adjust both wheels the same and check if the patio is level by almost closing the door and noting the gap between the door and the frame. Adjust the wheels until the gap is even all the way down. You may need to move the door locking keeper on the frame after adjusting the wheels. If this didn't solve the problem you may need to replace the patio wheels.
Removing the patio door to lubricate or replace the wheels
To replace the patio wheels the door must be removed from the frame. Adjust the patio wheels down to the lowest level by following the instructions above but this time turn the wheel adjusting screws on both doors anti clockwise. This will give you more room to remove the patio door.
Contact your local Glazing company and see if you can rent or borrow two glass lifting suckers from them, this will make the job a lot easier. If you can't get any Glass Lifting Suckers a garden spade can be used to lift / lever the patio door off the bottom track. Take care not to damage the door, frame or sill when doing this. You should be able to lift one side at a time and pull the bottom of the patio door toward you. CAUTION! Patio doors are heavy and I would not recommend trying to remove the door on your own.
Removing the patio wheels
Place the door on trestles and examine the patio wheels. It may be that they just need cleaning and lubricating. If they are damaged or the bearings have gone, you will have to replace them.
Remove the two screws holding the bottom section of the frame. There is one screw either side of the bottom section. Once these have been removed the bottom section can be prized away from the rest of the frame. Be careful not to lever against the glass or you could shatter it. When the bottom section is clear from the rest of the frame you will be able to remove the wheels. Some wheels have a screw holding them in and some are pressed into a holding bracket. If the retaining screws have rusted you can carefully drill them out, taking care not to make the hole in the bottom section any bigger. Contact your local Hardware Store, Glazing Shop or search on Google for replacement wheels.
After fitting the new wheels, make sure that they are adjusted completely flat or into the bottom section. This will give you more room when re-fitting the patio door. The wheels can be adjusted to the correct height after the door is fitted into the frame. Spray the wheels with a silicone lubricating spray. Before re-fitting the door, clear out any debris such as leaves and dirt from the track and spray the track, locking mechanism and top door channel with a silicone lubricating spray. Re-fit the door and adjust the wheels as described above.
