MW windows
This looks like our Series 850, but we'll need the diameter of the spring and length of the balance, including the top clip attachment and white bottom shoe. We will also need the width of the bottom shoe to determine the spring strength that you'll need.
Thanks for getting back to me. The overall length is 27 1/4", the bottom shoe is 1 1/4" and the diameter of the spring is 2".
Thank you. I'm afraid they don't make a balance in this length. This Series is being phased out by the manufacturer, but fortunately we do have a solution.
We believe you can use our S795-28 channel balance with with a 28C option. That option indicates a spring that can carry 18 through 23 pounds. You will also need to replace the pivot bar with either our 26-021 or 26-366. Finally, since ours installs using a screw tab instead of a hook, you'll need a 26-200 screw plug to pop in the hole in your jamb.
The major difference you have to look out for is hole spacing. You'll need one of these pivot bars to match the hole spacing already in your window. Only one hole has to match. If neither do, then you may need to drill a new hole for one to install.
Can you confirm the length of your old balance? They never made your type of balance in a 27-1/2" length, or any other odd-inch lengths. It would be either 26-1/2" or 28-1/2". I suggested it might be 28-1/2" just based on what I've experienced in the past.
The pivot bar just screws in at the bottom of the sash. You want to remove the old pivot bar and slide the new pivot bar in place.