Atrium non tilting single hung window balancer replace"

Do you happen to have an identical windows in the house with the balances still intact? If so, could we have you upload a photo or two showing that balance? If not, send us a photo of the balance you referred to, along with the measurements of the height of the visible glass, a photo of the track, the weight of the sash, the manufacturer of window, and a photo of the AAMA metallic sticker on the window. We will do our best to find what you need.

I'm afraid that stamp doesn't tell us anything relevant to this project. That stamp only tells us the calibration of the spring for that larger window, it's not an identification code or anything.

If the larger window is identical to the one that's missing its balances (aside from size, obviously), then show us a photo of the top and bottom nylon fittings on this balance. That's what determines Series. If these windows are the same brand, odds are they use the same Series balance.

Then, go back to the smaller window. Give me the exact weight of the sash and the height of the visible glass. That will allow us to calculate size and spring calibration.

Thanks for getting back to us. Is the glass size you provided only of the visible glass in the window? If so, typically the metal channel of a channel balance is 1" greater than the height of that visible glass. Therefore, for a window with 28" tall visible glass, you'd need 29" long balances. Based on the nylon fittings of the balance from the other window, you need an S395-29. If the window sash in question weighs 21 lbs exactly, then you need a stamp option of 2830. Let me know what you think.