I'm a handyman who has a customer with broken coil springs and carriers. I need 4 of the carrier 15-102, and 10 springs. But I'm not sure which weight springs. The windows are single hung vinyl, double glazed, and the outside dimension of the operable vinyl sash is 29.5 x 32.5. I neglected to weigh the windows while I was at the customer's house. I see no marks on the spring I took home with me to indicate what it might be. The customer had information from the the builder's supplier saying they can be either 3050 or 3060, and 3060 will work for either. But that doesn't correlate with what I'm seeing of your numbering system. I'm guessing the window is about 20 lbs, which would mean I need S145-4. Is that likely correct, or would you suggest a -3, -5, or -6? Thanks so much for any help you can provide.
Wayne
