Window will not stay up and slams shut

Thanks for posting. To my eye it certainly looks like the coils might be torn, and this would definitely be the cause of a window not staying open. It is best to remove the parts to examine them however. See the video below for a tutorial as to how. This looks like a 15-180 Pivot Shoe, which uses Series 190 Coil Balances. If your old coil housing is undamaged you can reuse it. Otherwise see the 15-186 Housing and 15-182 Drum. Let me know if you have further questions about this hardware.

Since the coil support is the 15-186, for a single coil, I suspect this was a single coil setup. Seeing if what's in there was torn would definitely confirm that. That said, I actually wouldn't get too caught up in the number of coils on each side of the window. More important is the 'spring weight' of the individual coil springs, or rather the weight each individual coil can support. There should be a stamp on the old spring, usually near the tongue, that indicates this. If there is none however, or you're unsure, just weigh the window sash these coil springs support. Give me that exact weight and I can calculate the spring weights you need. 

The reason spring weights are more important than the number of coils is sometimes replacement springs come in a larger variety of spring weights than were available to build your window. For instance, let's say your window used two 4 pound springs on each side of the window, for a total of 16 pounds of support. If there is a replacement spring weight of 8 pounds available, you could just use one new spring on each side of the sash. This would still equal 16 pounds of overall support, but use less parts to do it. Hope that makes sense. 

Hey there, this appears to be the same assembly you showed us last week. As such my recommendation remains the same. Have you reviewed the part numbers I recommended back on the 20th?

That's correct, we don't sell this as one complete assembly. We only sell the individual components separately. 

I apologize for any inconvenience this may cause.

Sure, that usually indicates a 9 pound calibration. Our S190-940 is rated to hold that exact weight per spring.

A good way to check is to weigh your sash on a scale. If it weighs 18 pounds, then using one S190-940 on each side should be perfect.

You're very welcome! Thank you very much for the business and please feel free to reach out if you had any other questions.