coil balancing spring

Question

my old springs are # 840 and is equivalent to 150 series but I don't know what lb it is. also need
2 ea. coil balance shoe 15-140
2 ea. coil bushing. 15-143
2 ea. coil bushing cap 15-144

Lauren · Accepted Answer

Hello, thank you for posting,

If the spring is stamped with #840, take a look at the S150-8 coil spring. This spring alone can support 8 pounds of wait. If one coil is used on each side, the sash weight should be 16 pounds. Please confirm and let us know if you have any additional questions!