Andersen 531 Narroline Sash Balancer

Perfect fit

This fit as predicted by Anderson references (always check!). My window was NOT the tempered glass. Some installation tips say that the top panel that covers these should be replaced, but it can go right back in. If you have never done these before, just watch videos, read instructions, and work carefully. You may have to remove trim on left side to get the track out. If you break a piece you probably can replace it, but not cheap! If you can afford it, do both since you already have the window apart.

We ordered the wrong size.

Fit perfectly

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.

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.

Fixed my problem with the window.

Installation was a breeze. You take the two window sashes out and the top cover for the balancers. The current balancer was just stapled into place so I had to pry it out. The new one went in with the screws provided. Now I dont have to use an old plastic bottle to hold the window open anymore.

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

it fixed the window