One sash balance is connected one is not




Thanks for posting. It looks like the Top Sash Guides on this window broke away. The Top Sash Guides keep the balances in place. They can erode due to age and sun exposure; when this happens, the balances can shoot past the sash and thus the window becomes jammed up, as I believe what has happened here. See the videos I have listed on this page which show how to remove and replace Top Sash Guides; they also show how to get the balance back into the correct position.
You will need new Top Sash Guides, so please remove an undamaged one, perhaps from the other side of the window or from an identical window in the house, and show us pictures of it from the front and side. We'll do our best to find a match from there.