Replacement Coil Balances for Thermolite double hung windows

Question

I need to replace several broken coil balances in Thermolite windows. I've attached pictures of one that I have removed that still works. In photo #2 there is an 8 stamped on the coil. Can you help identify the appropriate replacement parts that I would need to repair the window?

Also, the coil in the picture is from a smaller window. There are some larger windows that will need replacements as well but I haven't taken any apart yet. I'm assuming it will be the same plastic parts but the coil may have a different rating.

User submitted photos of a coil balance.

Paul · Accepted Answer

Thanks for posting. I recognize this spring. Unfortunately, it has been discontinued and is no longer available. However, the recommended replacement is our Series 150 spring. Check it out and see what you think. I also recommend that you consider our 15-140 shoe. You should be able to re-use your old supports, but just in case you want to replace them as well see our 15-143, 15-144, and 15-145.