If your older double hung windows are not working correctly, you may need to do some sash cord repairs to get those windows working like they should.
The window weights are attached to the window its self by means of a cord called a sash cord. The cord is fed over a pulley from the window to the weights. The weights are located behind the window frame in the wall.
As time goes by, the cords start to wear and sometimes break. The lack of the counterbalancing weights can make the window difficult to open. In addition, something must be used to prop open windows that have broken sash cords.
Sash cord repairs are easy to do.
Most windows have an access hole that is located in the lower part of the window behind the window frame. To access this opening you will need to remove the lower window pane.