Coil balance for vinyl double hung window

Home Owner from Ann Arbor MI

Aug 30, 2018 6:47 pm

First photo is left balance unit in a window that works. Next 4 photos show right and them left in window that won?t stay open. Seems like there are 2 coils on each side but one on each side is disconnected. On left side there look like a half round metal clip. It is broken off on right side.
Windows are probably at least 20 years old and I don?t know manufacturer. Bought and installed through Sears. Sash is about 36 x 25.

What do I need to fix both sides?

5 user uploaded images

6 Replies

Tom from SWISCO

Sep 7, 2018 8:11 am

Thanks for posting. I'm not sure exactly what's broken on your balance system, but it if it's just your coil springs then see our Series 180. I'm confident this is what you need. You'll have to get the number stamped on your existing springs to confirm what Series 180 option would be best.

If you need the other parts compatible with this spring, see our 15-087 pivot shoe/bottom housing, 15-086 top housing, and 16-024 bracket.

Home Owner from Ann Arbor MI

Sep 13, 2018 5:16 pm

I have removed the existing damaged balance and coils. On the balance holder is Pat. No. 5,353,548. Mechanism takes 2 coils on the one side with following info on them - Pat. No. 5,353,548. One coil has 446 35 and 6#; other coil has 466 35 and 6#. Coils have 2 round holes on the end.

Window weighed on bathroom scale is 25 lbs.

Appears that 6 lb 180 coil is what is needed - 2 on each side of window.

Also from your website additional items are 16-024 mounting bracket, 33-072. #8 x 3/8. ? SS pan head Phillips (for mounting bracket?), 15-086 Tandem coil housing and 15-087 coil housing pivot.

I?ve attached pictures of removed parts.

Does this seem to be what I need? I?ll be replacing both sides.

Gene H

4 user uploaded images

Tom from SWISCO

Sep 14, 2018 8:08 am

Thanks for getting back to us. Looks like all your springs are stamped with "6#," which I believe is the most important number. This is the weight rating. The equivalent of this stamp would be our S180-6.

If you use two springs per side, this will add up to 24 pounds of support. It's a pound less than your sash weight, but since your sash weight is an odd number this is probably as close as the installers could get. As long as your springs worked well in the past, then you can stick with this.

Those other products you picked out are all related, yes, but keep in mind that you only need to replace those parts that have broken. You can reuse the rest.

Home Owner from Ann Arbor MI

Sep 14, 2018 9:32 am

Would it be a good idea to get the S180-7? That would total 28, three lbs over the sash weight. Could the coils have broken because the 6 lb was ?stressed? more because of the window weight?

Tom from SWISCO

Sep 14, 2018 12:33 pm

Well, you don't want to go too strong, or else you'll find it difficult to close the sash. Personally speaking, I'd rather be one pound under weight than three pounds over. It's up to you.