Window won't stay open - some questions...

Thanks for contacting us! Yes, if your sash can't stay up then you definitely want new springs. Balance springs lose their tension over the years from constant use and eventually they just can't hold up the sash weight like they used to.

You mention you have the 15-191 pivot shoe, and that your spring is 3/8" thick with a #5 stamp, so I think our S160-5 is what you want to go with. If your pivot shoe is in good condition then you can definitely reuse it; that's one of the benefits of having coil balances. 

You do, however, want to replace the springs on both sides of the window. Even if the springs on one side are in good condition, they'll be weaker than the new springs simply due to use and age. This means the new springs have to work extra hard to pick up the slack and will eventually wear out faster than they would have originally. Does that make sense?

As for taking the system out, I agree that it's not always easy. The typical method is to feed the bottom shoe in first and do your best to snake the rest into the track. If you find it exceptionally difficult to do with three springs, then you could make the cut out a little larger. Watch the video below for how we do it. Just make sure not to make it too big. 

Yep, that definitely looks like the 15-191. As long as the spring is 1/2" thick then our Series 160 is a great choice.

You are very welcome. Please make sure and get back to us and let us know how everything works out.