Coil balance, vinyl double hung tilt in windows

A handy person from Chula Vista, CA 91911 says:
Good Morning,

I have numerous windows in my home and almost every one of them has broken coil balance springs. The top sash is difficult to hold up, and the bottom sash won't stay up when lifted. It is nearly impossible to push the top up while pushing the bottom down to get the locks to line up and lock the window.

I have had several window companies out and they basically do nothing. They just want to charge me thousands of dollars to replace the windows. The windows are in great shape except the springs are broken.

i am guessing the windows are at least 20 years old. There are no markings or labels on the windows so I do not know the brand. I have take some pictures of the parts, and was really hoping you could identify them and sell me high quality replacement parts.

Any advice or assistance you could provide would be greatly appreciated. The windows are large and heavy and seem to have double springs.
User submitted photos of window hardware.
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Paul from SWISCO responded:
You certainly don't need to replace the whole window, but I can understand that other companies had trouble finding this hardware for you. You have one of the first coil spring balance systems developed.

Fortunately, we can help. See our 15-140 pivot shoe, 15-143 and 15-144 coil spring bushing and cap, and Series 150 coil spring. You will need the number stamped on the old spring when ordering. For installation help, see the video below.
A handy person from Chula Vista CA says:
Hello Paul,
Thank you for this outstanding information. I think I am getting the picture here. As I look at the parts you suggested I note (you didn't mention this) a "coil support barrel". Is this something I need as well? Or is it not necessary for my application? Also, my problem is I have difficultly accessing the windows because it is a rental property. Is it ill advised to just guess the weight of the spring I need? The sashes are approx 36" wide by 30" tall and I would estimate the weight at about 15lbs. Dual glazed windows. Would I be ok just guessing? Or is the weight of the spring a critical aspect of the operation of the window? I would surmise if the spring is too strong the window would come up too fast and then be hard to close? And vise versa if the spring was too weak. Anyway, I think you get what I am trying to say. Thanks again for all the help and I look forward to your reply.
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Paul from SWISCO responded:
Thank you for bringing up the support barrel, 15-144. I did forget to mention it, but you'll need it. For a 36" X 30" insulated sash, I estimate the weight to be closer to 24 pounds, so you would use two S150-6 coil springs on each side of the sash. How's that sound?
A handy person from Chula Vista, CA says:
Hi Paul,
So per my initial photos does it look like the sash has two coil springs per side? I thought maybe one had dropped down from the top sash and landed on top of the bottom one, but I guess that's not the case. With this in mind, do I need a total of 8 set ups? 4 for the bottom sash and 4 for the top sash? Or is the top sash set up differently? I didn't even examine the top. Is the top and bottom essentially the same set up? Also, you said in your last response I need the 15-144 support barrel. Did you mean the 15-145? Thank you very much for your outstanding customer service and advice.
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Paul from SWISCO responded:
Thank you for your continued interest and patience with us. You may in fact need four coil springs for the top sash. Please inspect and check the spring number stamped on those springs. To put the coil springs together, you would need our 15-144 bushing cap along with our 15-145 barrel, and lastly our Series 150 coil springs. From there, snap it together with our 15-143 bushing. You don't need to replace all the nylon fittings, just the broken ones.
A quick learner from Chula Vista, CA 91911 says:
So it looks like I have a total of 4 set ups per sash, so that's 8 for one complete window.

I am not certain how I "stack" the two coil springs on each side of the sash. Do I "flip" one over so one spring rides along the front of the channel and the other rides along the back of the channel? I drew a rough sketch to illustrate what I am thinking. Do I have the right idea? Thank you very much.

Also, the plastic piece that fits into the base of the window sash(Pivot bar retainer?) ,does it look to you like I ordered the correct one as compared to the picture

Thank you for all your continued help. I have already placed an order (1008658). Can you take a look and see if it looks like I ordered the correct springs and related components. I took the spring number (5 and 8) off the broken springs (2 different size windows)

Thanks for all your help. You folks are awesome!
User submitted photos of window hardware.
User submitted photos of a pivot bar.
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Paul from SWISCO responded:
Yes, you would just flip the top coil spring to the other side just like how you showed.

The hardware you ordered seems to match quite well in relation to the coil balance, but I'm not sure about the pivot bar and retainer. The ones you bought from us look very different from yours so I'm not sure if they will work. I'm actually not familiar with the style you show. I suppose at the end of the day it would come down to how well the dimensions match.
A handy person from Chula Vista, CA says:
Thank you for your response. I should have my parts soon. Is there a lubricant or something you recommend for the channels where the sash slides? Since I will have everything apart, I will clean it all up and was just wondering if I need to use some type of lubricant? Thank you
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Paul from SWISCO responded:
You should start with cleaning the track with any household type cleaner. Next, spray the tracks with a silicone spray to lubricate. Do not use oil as it will catch dirt.
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