sears window coil balance

Hello!

No, you don't want the S140. This looks more like our 15-111 that's designed to use the Series 160 coil springs. For a new coil support, see our 15-150D or 15-150T depending on how many springs are used per side. There should also be a stamped code on the band of your coil spring that will indicate what coil weight you'll need. 

I'm afraid those numbers don't tell us what coil weights you need. If you can weigh your sash on a scale and tell me its precise weight, along with the total number of coils per side, I can calculate what weight is needed from there. 

Thanks, Andy! It looks like you may have a double coil support like our 15-150D. Since your sash weighs 20 pounds, you can use (1) S160-4 4.5 pound spring and (1) S160-5 5.5 pound spring on both sides of the window which totals 20 pounds of overall support.