Series 81OS - 19 2 St Caldwell

Hello there. I was going to say that this looks like an S380-20 or S385-20 Channel Balance, depending on the bottom shoe's depth (see the image below), and in either case you'd choose a stamp option of 1920. However, your detail that they are at the top and bottom of the sash, rather than side-mounted, is very unusual. Can you show me pictures of how the balances install? We may have more questions from there, but I want to see that just to confirm we know for sure what you're working with. Many thanks.

Comparison of the S380 and S385 balance shoes.

Well, I see a major problem right away. Someone installed a double hung window sideways in your shed. We can provide a replacement balance that will match the originals, but they aren't really going to work properly due to this fact. It's not going to fix the overall problem.

To clarify, the way these are supposed to function is the springs provide constant upward force to counteract the constant downward force provided by gravity. This allows a normal double hung window to remain raised when you open it; the balance is literally "balancing" the weight of the sash.

That's not going to happen on your window because there's no downward force to counter-balance. It's sideways, so all that's going to happen is the "upward" force of the springs will be constantly opening the sash to the side. It doesn't matter what kind of balance you install here, it won't work. 

There's unfortunately no alteration you can make that will get this thing operating properly. The root of the problem is that the wrong window was installed sideways. The only solution you should pursue is to install a proper sliding horizontal window, which will require replacing the entire thing.

I am sorry to be the bearer of bad news.

Sure, double hung and single hung both work under the same principle. The only difference is that in a single hung, the top sash can't move. In your case, that'd be the left sash.

As for reinstalling the window, I'm not sure how that would be possible, unless you tear down the whole wall and build it up again. To reiterate, you cannot use this window horizontally. It simply won't function. These are only usable in vertical applications. So in order to reuse this window for this wall, you'd have to reshape the wall to accommodate the new position. That is a huge amount of work and it may be more cost effective to just buy a new window and install it in the wall as-is.

Otherwise, if you still wanted to buy new balances, then my original recommendation of either the S380-20 or S385-20 still stands. You very likely have one of these two balances, but they aren't going to do you any good unless you find a way to turn this window 90 degrees in the right direction.

Anytime. Please feel free to reach out if you had any other questions.