Window balance replacements

Question

I placed an order for 4 27" SERIES 385 CHANNEL BALANCE in option 2630 and tried them on one of my windows. They seem to fit properly and allowed the window to slide up and down smoothly, however it would not stay up on it's own. I'm wondering if I need to get the heavier 2640 option, or even heavier? Thanks!

User submitted a photo of a window balance.

Paul · Accepted Answer

Yes, you need a stronger spring. At one time, balance manufacturers made specific spring weights. Yours is 36 lbs, so you can use our "2665" stamp option for a weight range between 33 and 36 lbs.