Nu Air Windows 1988 approx.

A professional from melbourne, FL says:
I need to rebuild the window parts for the Nu Air window in my home. I will need 2 each of the left and right parts pictured above 11/16" by 1-1/8 inch by 1-5/16" deep. Will send more pics for the rest of the parts
User submitted photos of a window balance.
A home owner from melbourne, FL says:
So I think I figured this out. Is it a 18-036 top sash guide?
A professional from melbourne, FL says:
OK so I think this is figured out, but I still need advice. I found stamps of 3530 and 3440 on the channel balances that came out of the 27 lb. window.

My assumption is I need to order either 3540 or 3440 for this window. Is there a way to ensure I order the correct one or should I be safe and order the 3440?

Your web site is really good, I typically go straight to online help as most webs are definitely poor at most other companies, but your company has done a fantastic job. Kudos to you guys.
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Tom from SWISCO responded:
Thanks for posting, and for the praise! Looking at your pictures, I don't think the 18-036 is the right choice. Your top sash guide looks like like our 18-178. Take a look and see if you agree.

As for the option, you should compare the weight of your sash with the weight rating chart we show for the balance you chose. However, I do have one question. You say you found two stamps, 3530 and 3440. Were these both in the same window? Two balances in one window should each have the same stamp.
A quick learner from Melbourne says:
27 pound sash should get the 3440 correct? Thanks for the quick response earlier
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Tom from SWISCO responded:
Yes. Two balances with the 3440 stamp option can carry a window sash weight range of 23 through 30 pounds.
A quick learner from Melbourne says:
Should I be concerned about using a 3540 or a 3440 for the window? Is there a proper method to measure to ensure the correct sash or does it matter?
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Tom from SWISCO responded:
Yes, absolutely. Like I said, two balances in the same window should have the same stamps. If those two stamps are accurate, then you have one balance that is 36" (3540) and another that is 35" (3440), which is no good.

If you don't know which one is the original, then it would be very hard for me to say what you need. I would recommend checking to see if you have an identical window elsewhere in the house that may have the same hardware.
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