Constant force window balance spring

Question

I need a lot of the these springs. They are for a 250 unit apartment complex and can't find them anywhere.

Jasmine · Accepted Answer

Thanks for reaching out! Your coil balance pivot shoes appear to be our 15-177. Take a look over the dimensions below to confirm that this is the right replacement for your existing coil balance shoe.

Alternate image for 15-177

These are compatible with the 1/2" thick Series 152 coil balance springs. To determine the correct spring strength for a particular sash, you'll need to look for any stamps/markings on the metal coil(s) in the window. If there are no stamps/markings or they are hard to read, you'll need to obtain the exact weight of your sash. Once you have the sash weight, you'll divide it by the number of coils in the window.

You may also need the 15-143 coil bushing, the 15-144 coil bushing cap, and the 15-145 coil bushing along with the 33-072 to secure the coil to the shoe.