Do you sell this 29 9 KW CMC 11 balance?

Question

I have a double hung window and will not stay open. The balance spring cover has 29 9 KW CMC 11 printed on it.
The window size is 51 1/2" x 32".
Do you sell such a window balance spring? If not, what might be a replacement?

Tom · Accepted Answer

Looking at your photos, I don't think the balance is broken. It seems the top sash guide is what broke, which means it can no longer retain the balance, causing it to shoot up to the top of the track. The balance is probably still in good working condition.

We can still help, but you will need to remove an undamaged version of the top sash guide from the window and show me a photo of it by itself and without obstruction. Please show us a clear shot of it from the front and side; think of it like a mugshot.

The video below will clarify what the issue is.