window coil balance

Question

Need to replace this double coil balance. They have letter code rather than number. Cover says G & H but coils themselves are H & HL. I cannot find an alpha to numeric conversion table anywhere. ?? G = 7 and H = 8 ?? Assume the "L" in HL means long tail as it was the upper coil. I will need the entire assembly as cover (2 screw hold down) is destroyed and shoe's pivot pin is broken. Coils appear OK and shoe itself other than pivot is OK. Can you provide some direction please. I have looked everywhere for these but cannot find exact copy. Measurements are: Coils - 0.37, shoe - 1.5H, 1.25W, .54D. Cover is 1.25W. Tension pad comes out back of shoe.

Thanks Paul

Bob · Accepted Answer

Hi Paul. This pivot shoe looks closer to our 15-177. This shoe is compatible with our Series 152 Coil Springs. For the housing with the Series 152, we recommended individual housing for each spring: see our 15-143 bushing, the 15-144 bushing cap, and the 15-145 support barrel.

As far as the spring weights you need, based on experience I think you're correct that the stamped letters might be converted to numbers, and that therefore you need an S152-7 (7 lbs of support) and S152-8 (8 lbs of support). To be safe, I'd weigh your window sash. If that exact weight is 30 lbs, dividing that weight in half would give you 15. That would mean you'd need 15 lbs of support on each side of the sash, which would confirm you need the S152-7 and S152-8 on each side of the sash.