Fiberlux top windows sliding down

Question

We had Fiberlux replacement windows installed.  They worked fine for a while, but now the top windows sometime slide down.  I can't figure how to tighten them.  They have a long plastic piece on the uppers with a long cork-screw type apparatus along the lowers.  How do I adjust this?

Paul · Accepted Answer

Usually when a window droops down like you describe, the culprit is the balance. If memory serves, Fiberlux used a spiral balance similar to our Series 600. Can you confirm? If so, you could likely get away with adjusting it using a tool like our 75-006, rather than replacing it outright. See the guide below for more information.

Guide: How to adjust a spiral balance on a tilt window