Coil balance replacement

I believe we can help, yes! Please see our 15-087 pivot carrier and 15-086 secondary carrier. These are both compatible with our Series 180 coil spring.

Please let me know if you had questions about these products or any other.

The window size unfortunately does not tell me what weight option to choose for the Series 180. You will need to refer to the stamp printed on the band of the old spring. It should be near the two holes at the end. 

If you are unable to do that, then the only other method is to weigh the sash on the scale and then divide that by how many springs support it, in total. For example, if your sash is 10 pounds and you only have 1 spring per side, then you would divide 10 by 2 to get 5. In other words, you'd need a 5 pound spring on each side.

There is no other method by which you can determine the calibration of a coil spring. You either have to get the stamp off the original or you need to weigh your sash on a scale. Your next step will need to be one of those two things.

Sure, so in that case you can use two 5 pound springs her side, or the S180-5. That will give you a total coverage of 20 pounds, which should be perfectly sufficient.