Why does your sliding patio door jump off the track?

The symptom

The sliding panel has come off its track, or keeps trying to. It tilts, drops at one corner, scrapes along the sill, rocks when you push it, or stops partway and will not go back. Sometimes it runs normally for a week and then jumps again.

This guide covers that one symptom: what "off the track" means, why you should not lift the panel back yourself, the causes a technician works through, and what you can check with the door left where it is. It is not a repair manual.

What "off the track" means

The sliding panel rides on rollers, the wheels set into its bottom edge. The rollers run on the sill track, which JELD-WEN defines as the track on the sill that guides the panel as it opens and closes. A second track in the head of the frame guides the top of the panel. A door is off the track when one or both rollers are no longer sitting on the sill track.

Manufacturers list this condition by name. JELD-WEN's wood patio door guide gives "Rollers may be off the track" as a possible cause of a door that is stuck shut. Andersen says the moving panel on its gliding patio doors rides on two rollers on the underside of the panel.

Do not lift the panel back on

JELD-WEN's remedy for rollers that are off the track, in its wood patio door guide, involves lifting the glazed panel. Its vinyl patio door guide explains why that is not a job for one person at home:

"Patio door panels are very heavy. Removal and installation require two or more people."

Both guides add that panel removal can be awkward and could cause injury or damage to the door. The vinyl guide marks the procedure for removing the sliding panel "For Professionals Only." This site keeps to that line and gives no instructions for lifting, tilting, or removing a panel.

Do not force the panel along the sill, lever it with a tool, or try to walk it back onto the track.

What a technician checks, and why

The manufacturer documents we opened name this condition and give no cause for it. JELD-WEN's table lists only the remedy.

What the documents do describe are the faults behind a panel that drags, sits crooked, or will not close. Those faults are in the same parts that carry the panel along its track, so they are what a technician checks. That link is this site's reasoning. It is not a manufacturer's statement about why a panel comes off.

• Something in the track. JELD-WEN lists obstructions, debris, and leftover shipping blocks among the causes of a panel that will not open or close, and obstructions among the causes of a panel that looks crooked in its frame.
• Rollers set too low or unevenly. JELD-WEN says rollers adjusted too low can make the panel drag on the lower track, and that one roller may need raising while the other is lowered. Its troubleshooting table answers a panel that drags on the sill, or does not sit square in the frame, with roller adjustment.
• Worn or damaged rollers. Andersen says rollers may wear over time, and that rollers which are hard to spin, chipped, cracked, or worn need replacing.
• A damaged track. Andersen has the sill track cap, the part of the frame the rollers sit in, checked for dents and bad scratches. If the cap is damaged, it is ordered along with the rollers.
• The frame. JELD-WEN lists improper installation and a bowed frame among the causes of a panel that will not close, and says a door that fails to operate properly needs its installation inspected. Andersen says a door installed out of plumb, out of level, or out of square may have a panel that glides too quickly.

Which of these applies to your door is for the person who inspects it to say.

What you can check safely

All four checks are done by looking. The panel stays where it is.

1. Look at the bottom corners. Is one corner lower than the other? Is the bottom edge sitting over the track, or beside it?
2. Look along the sill track. Debris, a dent, a flattened stretch, or deep scratches are visible from above. Look and do not feel, because a damaged track can have sharp edges.
3. Look at the gap beside the panel. Andersen's check for alignment is to open the panel slightly and compare the narrow gap between panel and frame from top to bottom. An uneven gap means the panel needs adjustment. Do this only if the panel is on its track and moves freely.
4. Note when it happens. Does it jump at the same spot each time, or anywhere along its travel? Did it start after something specific?

If the panel is still on its track and only threatens to jump, clean the track before anything else. Andersen's method is a soft-bristle brush with warm, mild soapy water, a rinse with clean water, and letting the track dry before the door is closed.

Take photographs of all four. The photo guide lists what else to capture.

Until it is repaired

If the panel is off its track, stop using that door and keep children and pets away from it. Use another door.

Check whether it still locks. Andersen notes that after the rollers are adjusted, the latch receiver may need adjusting too. Panel height and the latch are linked in that way, so do not assume a panel that has dropped still latches.

What a technician does

A technician resets the panel with help, then finds out why it came off.

• The rollers are inspected. Andersen states that the panel must be removed to inspect the rollers.
• The track is checked for dents, scratches, and debris.
• Roller height is set so the panel clears the track and sits square.
• The frame is checked when the first three do not explain the problem.

If rollers are replaced, JELD-WEN's procedure starts with removing the sliding panel and laying it flat.

Where to go next

• The track repair page covers a dented, worn, or lifted track.
• The roller repair page covers worn or badly adjusted rollers.
• The alignment page covers a panel that sits crooked.
• If the door drags but has not left its track, start with why a sliding door is hard to open.
• If it grinds as it moves, read the grinding noise guide.
• The glossary explains the part names used here.

To ask about a repair in Plano, Allen, McKinney, or Frisco, describe what you saw on the contact page. The operator reviews every inquiry and replies with the next step. Sending the form is not a booking.