Spiral Balance

A handy person from San Antonio, TX says:

Hi, I am a big DIY guy but have zero experiences with "spiral balances". I have a non-tilt window that needs two balances installed. I removed the screws from the tubes on both sides. I would like to replace both. Whats weird is that none of the windows in my home(18+) have plates on the bottom of the sash to hold the spiral. I have watched videos on the internet and spoke with one of your reps about this. However all of my windows have an open channel on the bottom of the sash, no place to mount a plate and quite frankly they do not appear to be designed to support a plate. The small "brass" key on the end of the spiral appears to just fit into the bottom of the sash channel(if that makes sense)?? see pictures

I measured the removed tube and it is 29" with an orange tip.

I did have a slight tug of war with the tube that I removed. The tube and inner spring remained inside but I had to lift the window and pull the spiral from the bottom as seen from the attached pictures. I am not sure if I removed correctly and what is the correct way to replace. I apologize for the lengthy email but want to be sure I understand all before moving forward....measure twice, cut once!!

Thank you,


Thumbnail of the uploaded file named right_balance opening-2.JPG
Thumbnail of the uploaded file named under sash.JPG
Thumbnail of the uploaded file named left_spiral end.JPG
Thumbnail of the uploaded file named right_tube mount.JPG
Thumbnail of the uploaded file named right_balance opening.JPG
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Tom from SWISCO responded:

Thanks for contacting us, Milton. It looks like your bottoms ash corners have brackets like our 17-010 or 17-025 (among other examples). Your sash wasn't made to come out, so these are very difficult to repair or replace. Fortunately, yours are in good condition.

These work with the tip of the balance just clipping into the slot. Your balance i s likely our S400-29, though you may want to measure the diameter of your balance tube just to confirm that it's 3/8".

Replacing these balances can be tricky, since the sashes can't come out. You just have to try your best to work it out from the top. There's no secret to it, it just takes patience. If the balance is especially long there's a risk it could hit the top of the frame, which is even more frustrating, but hopefully you can wriggle it out.

The reason it's so difficult is because the original manufacturers would rather you go to them to buy a whole new window whenever even small parts break. We don't believe in that kind of design practice, of course, so we've found little tricks around it, but they're not ideal. Hopefully you'll be able to get it but let us know if you run into issues.

A handy person from San Antonio, TX says:
Hi Tom,
Thank you for the prompt reply. Ok, I get no secret, just patience...which I have!! When I tried to remove the balance from the right-side I started pulling on the tube(3/8-29") from the top of the sash. But the "spiral" seemed to be hooked on the bracket. So the tube and spring removed from the top and I pulled the spiral out from the bottom.

When I go to replace are you saying the "entire" unit is feed "patiently" into the sash channel from the top? I think it would be a no brainier if that brass key at the end of the spiral was removable. That "T"/cross shape is kinda wonky if you know what I mean?
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Tom from SWISCO responded:

I do know what you mean! These can be vexing, as you know all too well. If there is some kind of obstruction on the sides of the sash then it would absolutely inhibit the process we normally use to install these.

This is a tough one. You won't be able to remove the inner spiral rod from a new balance without irreparably damaging it, so putting it in from the top is your only option. The only hope we have is that pushing the butterfly clip down from the top will be easier than pulling it up from the bottom. I'm sorry we can't give you an easier solution! We just have to make do with the admittedly crummy design the original manufacturers used for these windows.

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