11 Year Old SIlverline 2900 Series Single Hung Window Balances

I'm not sure what the issue may be. If you have a balance like our Series 795, then it's possible that the hook on the shoe that clips over the rivet (see the video below for an idea of what I mean) snapped.

That said, it is also odd to me that the shoe would fail before the balances. It's not unheard of, it certainly happens, but it's not common. 

One explanation would be that your springs aren't the proper calibration for your sash weight. If the balances aren't balancing, then there could be undue strain to that exact part of the shoe. It would be forced to withstand either more weight from a heavy sash or more pressure from a too-strong spring. To confirm this, please give me the exact weight of your sash and the stamp printed on the balance's metal channel. That will let me calculate whether or not your spring strength is right for the job.

Then again, all of what I just said is just a hypothesis. It's also possible that the plastic is poor quality and it broke because it was 11 years old. I think I'll need more data before I can say for sure. Once you get me that sash weight and stamp, I'll be in a better position to make a judgement. Photos of the hardware in question would also help. Let me know!

It looks like the S795 was originally used for your 2900 Series window. If the balance channel is still working, then the T-Lock replacement would be our 15-195 shoe. You'll need to unscrew the balance channel from the window and install the 15-195 T-Lock shoe by following our video below. The center cam of the 15-195 is die-cast, while the rest of the T-Lock shoe is nylon. If you want to replace the complete balance, we'll need to know the metal channel length. Thank you!

Thank you! Please do. I'm happy to help in any way I can if you need it.