Emily from SWISCO responded:
August 21, 2023
Thanks for reaching out to us! I recommend our 15-087 pivot shoe and 15-086 housing. With a 30-pound sash, you can use one S180-9 9-pound spring and one S180-6 6-pound spring on both sides of the window. Having 15 pounds of support on each side of the window sash will total 30 pounds of overall support. |