Old Coil Balance System

Thanks for posting. I'm not quite certain about the identity of this coil balance system, which looks to be an older design; but I'm pretty confident we can find a replacement. Can you just tell me the width and thickness of the pivot shoe? The identity of the pivot shoe determines the identity of the entire coil balance system. From there, we'll do our best to find the right substitute for you if we have it. Thanks.

Perhaps I can be of assistance. Your pivot shoe looks similar to our 15-199. Like to see the pivot bar to make sure it will fit. The 15-199 pivot shoe uses S160 coil springs where the first spring hooks into the pivot shoe and the next one hooks to the rectangle hole in the bottom coil spring and the next coil spring below that one. The coil spring cover is 15-150T. For a 27 lbs. sash, you would need two S160-7 coil springs, two for each side of the sash. This gives you a support fora  28 lb sash; plus or minus one pound difference is acceptable with these coil balance systems. Let us know if you have further inquiries. 

Ah, I see. I'm afraid we don't have a Series 140 that will work for that strength window. I think your best bet is still our 15-199 shoe, 15-150T support, and an S160-9 spring knowing now that your sash is 54 pounds. These carry 9 pounds each, so six of them will support that weight.

Ah, you're right. I'm sorry about that. Doing a little math, it looks like your best bet is to use four 9.5 springs (two on each side) and then two 8.5 springs (one on each side). That adds up to 55 pounds of support which should be fine. Just make sure the springs are symmetrical.

The bottom spring connects to the shoe, and then each spring stacked above that connects to the spring below it.