Andersen 531 Narroline Sash Balancer

Work great

Fixed my problem with the window.

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

Appears to be a genuine Andersen product. It was kind of a pain to replace due to the size of my window and the fact that the window had extension jambs, which means you cannot full remove the header piece, but the window works like new now that it is done.

The perfect fit

Easy installation once you get the sashes out of the window casing. Good directions on YouTube and on the direction sheet that came with the product.slightly different construction than the ones that were in the 40-year-old window. Slight modifications made them fit just right.

Works well to replace the counterweights in my Anderson windows.

it fixed the window

Be aware that to install this in pre-1980 Andersen windows you will need to chisel or rout a 3/16 recess in the window frame to install to accomodate the lip with the screw holes on one end of the balancer as stated in the instructions that come with the replacement. I used a sharp 1/2 wood chisel. I strongly recommend watching the video for this project on Andersens, Swiscos or Youtubes websites. Its not as easy as the video makes it look. Particularly with smaller windows. Always replace both balancers. Once installed, the balancers worked fine.

Almost as easy to install as the videos show. Taller windows are easier to do as you have more room to bend the plastic jamb covers. best to do in warm weather when plastic is more pliable. take your time, dont drop the sash. An extra person to hold the sash during the procedure might help. works great.