If the window cannot be easily operated, check for any outside obstructions and remove. If the window resists closing, check for obstructions between the moving aluminium sash and the fixed timber mainframe. Ensure that no debris is obstructing the slide motion of the moving arm.
If you are still experiencing problems, check that the outside of the window is hanging square. If there appears to be a problem, some adjustments can be made using guidance from our Installation Guide, or you can call the VELFAC After Sales Service team for assistance.