Coil Balance Spring for Certainted Double hung Window

Home Owner from NJ

Apr 28, 2019 11:41 am

Both coil balance springs broke on a Certainteed double hung window. The only number I see stamped on the coil is 10. Is there a Model S170-410? or will a S170-409 be compatible.

GM

13 Replies

Casey from SWISCO

Apr 29, 2019 11:21 am

Unfortunately, I'm not able to confirm the series of coil you need without first seeing the coil you have now. If you would like to send us over a photo of the coil and the pivot lock shoe it attaches you, we'd be happy to help further.

Home Owner from NJ

Apr 29, 2019 5:27 pm

I took the window apart:

1. A186160 pivot lock shoe
2. Short tongue SS 3/4" stamped 10 J

Tom from SWISCO

Apr 30, 2019 1:49 pm

I'm afraid we don't have a 10 pound spring for this balance system. The 9 pound spring may work, but it will be a little weak.

Another solution would be to use two 5 pound springs. Specifically, our S170-405 on the bottom and an S171-405 on top. You'd also need a new 15-156 cover and 15-157 bushing. See what you think.

Home Owner from NJ

Apr 30, 2019 5:22 pm

Thanks for the response. Both springs broke on the lower sash whuch are independent of the upper sash; so I don't think 2 5 lbs springs are correct. The window is closed 98% of the time and just needs to hold the window open so it does not fall down immediately. I think the 9 pound spring would be acceptable. What do you think?

GM

Tom from SWISCO

May 1, 2019 8:09 am

If you don't think the original springs were the right calibration, then you should weigh your sash on a scale and be 100% sure. That's the only way to know for sure that what you're buying will work.

Once you have the exact weight of the sash, you simply divide it between the number of springs used to support it.

I hate guessing when it comes to balances. I've been personally burned too many times whenever I try. In my experience it's always better to know what you're dealing with and get the precise weight of the sash; measure twice, cut once and all that.

Home Owner from NJ

May 1, 2019 6:24 pm

The window sash weighed ~ 18 lbs measured on a bathroom scale. A 9 lb coil balance should do the job for both sides. Do you agree?

GM

Tom from SWISCO

May 2, 2019 7:01 am

Yes, okay then! If your window sash weighs 18 lbs, and assuming you're working with Series 170 Coil Springs, then (2) of the S170-409 will work for you.

Home Owner from NJ

May 2, 2019 6:06 pm

Thanks for the continued discussion in hopes of getting it right the first time.

Many thanks! I will place the order for (2) S170-409 coil balance springs.

GM

Tom from SWISCO

May 3, 2019 8:03 am

Great! Always my pleasure to help. Let us know if you have any other questions. Thanks for your business, we really do appreciate it.

Home Owner from NJ

May 6, 2019 6:47 pm

Recived the replacement coil springs today. Installed them in less than 10 minutes, window works like new again!

Thanks again and I will certainly recommend SWISCO to others.

GM

Tom from SWISCO

May 7, 2019 7:39 am

We are so happy to hear that everything has worked out for you. We look forward to working with you on your next project.

Tom from SWISCO

May 7, 2019 7:48 am

That's awesome, thank you! We appreciate your kind words and look forward to hearing from you again. If you ever need anything else, you know where to find us.