Andersen 531 Narroline Sash Balancer

Perfect fit

Fit perfectly

I liked that it went in without having to modify the window

The perfect fit

Works well to replace the counterweights in my Anderson windows.

Mechanism failed at 18 year point. Needed to match exact window with balancer. Lots of good encouragement on the YouTube and from Andersons website for DIY. Hardest part was removing side vinyl/plastic panels without cracking or scraping casement. Patience and persistence paid off.

the hardest part is to remove the plastic track. i put some dawn detergent on it to make it slippery to take off and then to wiggle it back into place. the balance was an exact match and fit into the available slot without any additional work. the window functions better than new.

We ordered the wrong size.

I had an old Anderson 523 Sash Balancer with a broken string. This said it was compatible for the model 523 so I gave it a try. The old one had screw holes through the center of the unit and these have holes at the end through a tab that my older ones did not have. These fit perfectly in the old space. The tabs do extend out slightly but they screwed in just fine and I did not need to notch any of the frame. There is an awesome how to video I found on U Tube that shows how to replace these. Just search how to replace an Anderson window balance. The window works smoothly now and this is much easier and cheaper than replacing a window.

Direct replacement window operates like new. Make sure you use measurement chart for correct part number