Window sash spring replacement

Question

I work at a mid century modern house that is a bed and breakfast. The house was built in 1948 and has Alwintite windows throughout. I am looking to replace some of the sash springs. I attached a couple of pictures of one I removed because it came out through the bottom of the sash. Since I am unable to remove the window and weigh it without dismantling the entire thing, perhaps you could let me know what color tip spring to purchase? The window sash is 35

User submitted photos of a window balance.

Paul · Accepted Answer

Your sashes aren't made to come out unless you dismantle the master frame, which is a time consuming job. I would recommend our S500-29 with a red tip color option.

With someone helping you, you will need to drop the new balance in from the top of the sash, screw it in at the top, then let the spiral drop down. You will then raise the sash and, while someone holds the sash in the open position, spin the spiral up to the bottom of the sash. Finally, with our 75-004 tool, give the balance about three turns to charge it and lock it to the end into the sash clip.

Let me know if you have any more questions.