31 5 JO Caldwell window channel balancer replacement

Thanks for writing in. I can't say for certain what you have without seeing pictures of the nylon fittings at either end of the balance. However, based on your description you might have either our S380-32 or S385-32. The only difference between these two balances is the 'depth' of the bottom nylon shoe, so compare both with your old hardware to see if one is a match. Also confirm that the metal channel, not including those nylon fittings, is indeed 32" long. Finally, you'll need to select a stamp option. Your stamp code of 31 5 conforms to our stamp option of 3150; but this is for a window sash in the weight range of 28 through 32 lbs. You say your window weighs 19 lbs. Did you ever have trouble keeping your windows closed before this? If so, it's possible your balances had too strong a calibration. Confirm your window sash's exact weight; if it's indeed precisely 19 lbs, you'd want to use the 3130 instead.