Replacement for coil balance spring

Hi Ron. The stamp numbers that are sometimes on the coil springs tell you essentially the weight each individual spring is designed to support, but not necessarily the identity of the springs. To know what kind, or what we call Series, of springs you need, show us the pivot shoe that the springs attach to. The pivot shoe is the piece with the metal cam from which the window sash tilts. The identity of the pivot shoe determines the identity of the coil balances. 

Now, once you know that, you'll still need to know the weight you need the coil balances to support. In lieu of any stamps on the springs, give us the exact weight of your window sash, and we can work out what you need. Thanks.

Thanks for getting back to me, Ron. See our 15-192 Pivot Shoe. This certainly looks like your old shoe, minus the different cam. To be safe, can we a picture of the pivot bar your old pivot shoe's cam interacted with? Preferably removed from the window? That we can tell you whether you're safe using the same pivot bar, or if you'll need to replace them to accommodate the 15-192's different cam. 

The 15-192 is compatible with Series 170 Coil Springs. If your window weighs exactly just over 8 lbs, then two of the S170-334 4 lb Coil Springs, one for each side of the window sash, should suffice, as this will equal 8 lbs of overall support. Let me know if you have any other questions.

There should be a metal pin (in a few cases, it's made of nylon) that connects the window sash to that cam within the pivot shoe. This is called the pivot bar. See if you can show us that removed from the window. 

I'm afraid those components are for the housing that goes around the coil spring itself. The pivot bar will be literal bars or pins in the bottom corners of the window sash. You can see our selection of them here for reference.

Hey Ron. See our 26-040. This looks like it has a similar 'u' shape channel to your old pivot bar. Just go over the dimensions to confirm it would match the hole spacing of your old pivot bar. 

Sorry if this got lost in the shuffle of our discussion: The 15-192 is compatible with Series 170 Coil Springs. If your window weighs exactly just over 8 lbs, then two of the S170-334 4 lb Coil Springs, one for each side of the window sash, should suffice, as this will equal 8 lbs of overall support. Let me know if you have any other questions.