3 sashes per window - each sash 30"W x 24"H
2 sets of windows
Hello,
I believe that you can use the S500-25 red tip spiral balance with the 17-012 bracket to replace the old-style balances shown in your photos.
See generic instructions for installing these balances below:
To install these balances, you would drop them in from the top on the side of the sash. You'll use the #33-011 screw to attach the balance tubes at the top of the jamb. Then, raise the sash and have someone hold it up while you attach the bottom bracket #17-012 with #33-071 screws while the U-shape opening corrals the spiral. Use your finger to raise the spiral to the bracket. Next, attach the 75-004 charging tool and turn the spiral clockwise three turns before hooking it to the fork of the bracket. Repeat the other side and try the sash. If the sash creeps down, raise and hold up the sash and give the balances another turn or two.