Cool balance assembly
Hello there. This looks like a 15-087 Pivot Shoe, which works with Series 180 Coil Balances. For each replacement coil spring you have to choose a spring weight; this reflects the weight the individual spring can hold. The numbers on the 15-087 shoe are often not reliable to go by; to know what you need, weigh the window sash the coil springs support. Give me that exact weight and I can calculate what you need.
Thanks! I'm glad you checked. For a 12 pound sash, I suggest using one S180-06 per side. That will give you 12 pounds of support exactly.
Your existing stamps indicate a 7 pound calibration, which would give you 14 pounds of support. Being two pounds stronger than the weight of the sash might not be the end of the world, but the sash would become more difficult to close. In more extreme cases, the sash could even open on its own.
That will have to be your decision. I outlined the potential consequences of going that way in my prior post, but you will need to make the final decision.
If the given weight is just an estimate, then I highly recommend actually weighing it on a scale so that you know for sure. You never want to guess.
Thanks for confirming. In that case, use the 180-07 7 pound Coil balance spring. Let us know if you have further questions!
Great! We'll be here if you need anything else.