Broken Balance

Thanks for writing in. Could you show us a clearer picture of the clip at the end of the nylon cord? I believe this may be a Series 770 Channel Balance, but it would best to see this clip to confirm. Could you also measure out the length of the metal channel? Finally, if there is no stamp code on the channel, you will need to provide the exact weight of your window sash. Many thanks.

Thanks for getting back to me. Yes, as I thought, this looks like a S770-35 Channel Balance. Just go over the specifications listed on the product page to be sure. Your stamp code indicates you'll need to select a stamp option of 35C. Let us know if you have any questions. 

No, the tension in a channel balance cannot be adjusted in any way. The 75-005 is a charging tool for spiral balances, which have a different configuration than channel balances. We recommend the 75-005 for installing the S770 only because it is helpful for attaching the clip to the pivot shoe; but otherwise it has no similar function. Trying to adjust the channel balance's tension in any way is not only impossible; it's very dangerous and frankly a good way to lose an eye! These are solid steel springs under dozens of pounds of pressure; they are not meant to be modified. 

The stamp '35C' on your old balance indicates the spring strength it was calibrated for; this is why we recommended the S770-35 with a stamp option of 35C. Did you ever find your windows difficult to open or keep open with those balances before they broke? If so, it's possible they were too strong for your window to begin with, and you would need to weigh your window sash to know the proper stamp option.