Hello, thank you for posting,
To further review, we will need to see the pivot shoe that the coil spring is attached to. The window sash will need to be removed for a view of the pivot shoe. From there we can determine which series you need for your window. Thank you!
Thank you,
We do not carry your exact pivot shoe, but we recommend reviewing the dimensions of the 15-177 that is compatible with the Series 152 coil springs. These work a little differently than your old springs, because the spring screws to the shoe instead of hooking onto it, but it should still work.
If you need assistance with choosing the correct weighted coil option, please provide the weight of the window sash to move forward.
Also review the 15-143 bushing, 15-144 bushing cap and 15-145 support barrel.
Thank you,
For a 13-1/2 pound window sash, you can use (1) S152-7 coil spring on both sides of the window to get you 14 pounds of support. Please review and let me know if you have any additional questions!
