On my door the holes had plastic plugs in them.
Sliding glass door adjust.
These holes hide the adjustment screw for the coordinating rollers.
As the framing inside the door opening settles the tracks raise or lower with the floor.
First locate the screws on the bottom of your sliding glass doors.
Spray the entire sliding glass door track with a silicone based lubricant to ensure your door glides smoothly.
You can alter the height of these rollers by accessing the adjustment screws which are set into slots on the door s outer edges perpendicular with the rollers themselves.
On the bottom portion of your sliding glass door you should see a small hole on each side of the door.
Inside a standard sliding glass door there are adjustable rollers that help it slide back and forth on the track.
They may be covered by plug covers.
All it takes is a few turns of the adjusting screw on the edge of the bottom rail of the door.
There are holes on your sliding glass door that conceal the adjusting screws to these rollers.
How to adjust sliding glass doors.
Over time the framing of your home settles.
Most sliding glass doors contain two sets of rollers one on each side of the bottom of the door.
Every standard sliding glass door has adjustable rollers that help it slide back and forth within the track.
Adjusting the rollers on your pella sliding doors raises or lowers the door panel as necessary to get the door working.
Be sure to wipe up any excess that gets on the floor it can make the floor very slippery adjusting the height.