Window springs top and bottom
Hello! Looks like you have old Simonton brand coil balances. The bad news is that these aren't really made anymore and it's not something that we can supply. The good news is that we have a more modern balance assembly that works just as well, if not better. It just takes a little work to get it installed in the window.
The video below will walk you through the process each step of the way.
1) What weight would you recommend for the spring? it looks like the vary widely https://www.swisco.com/srch?q=s159
2) The video showed replacing this assembly for the lower window - I assume its the same or similar and same parts to do top window as well? Thanks.
Sure, in order to choose the proper weight option for the new spring you would need to weigh your sash on a scale, then divide that between the number of springs supporting it. For example, if your sash weighs 11 pounds, then you want two 5.5 pound springs (one for each side).
Your divided sash weight may not land perfectly on one of these weight options, but as long as you get as close as possible then you should be okay.
The method for installing a new balance for the top sash would be the same as the bottom, yes.
That's great to hear! It's always a relief to know things went smoothly, especially when it comes to special adaptations like this.
If you ever needed anything else, please let me know. We're always here to help.