replacement spring

Question

Hello Emily the expert ,
There are two picture. showing my problematic coil balance, with no names, numbers or markings on any of the parts, as I can see. Only a number "8". The window sash weighs 30 lbs. Please help to identify the part (spring) to be ordered, or other ways to solve the problem. The window won't stay in place and simply fall. Thanks in advance for your help.
-Yujun (Eugene) Zhang

Tom · Accepted Answer

Hello, Yujun! We sell this balance assembly, but only the individual components as separate products. See our 15-087 pivot carrier, 15-086 secondary carrier, and Series 180 spring.

Based on your description it sounds like you really only need the spring. As long as the rest of the assembly is in good condition, which appears to be the case, then it can be reused.