A customer in Hatfield got in touch because the patio door had become difficult to close and was giving her problems.
Once on site, I removed the multipoint mechanism from the door and the fault was immediately visible. A small piece of metal had sheared off inside the gearbox and was left dangling around inside the case.
At that point there was no sensible adjustment or lubrication fix to make. The gearbox itself had failed and needed replacing.
I had the correct replacement in van stock, fitted the new gearbox and tested the complete multipoint system.
Before finishing, I also checked the door for alignment issues and lubricated the moving parts so the replacement gearbox was not being asked to work against unnecessary resistance.
The patio door was then opening, closing and locking smoothly again.
