The window does not stay open

Thanks for reaching out to us! It sounds like the balances may need to be replaced in the window. If you've attempted to add tension to them and they are still slamming down, they're likely to be damaged.

You'll need either the Series 600 or the Series 900 Spiral Balance to replace what you have. To determine the correct replacement, you'll need to confirm its length and diameter. 

You may also want to check to see if the pivot shoes need to be replaced. These may still be installed in the window track.

I've included tutorials below with instructions on how to remove/install the hardware and what we'll need to identify the balances.

Please let me know if you have any questions.

Thanks for confirming. You'll need the S900-30 Spiral Balance to replace yours. The tip color appears to be white, so I believe you'll need the red tip option. Be sure to double check that your sash weight falls between 10 to 22lbs.