Salesforce

Replace Lock on A-Series and 400 Series Casement or Awning Windows

Printable View
« Go Back
Fields
Replace Lock on A-Series and 400 Series Casement or Awning Windows
000003459
New Section

 

Andersen® A-Series and 400 Series casement and awning windows manufactured after 1995 use a concealed window sash lock.

Install a Concealed Lock on Andersen® A-Series and 400 Series Casement or Awning Windows

This article provides you with resources for ordering and installing a concealed lock on A-Series and 400 Series casement or awning windows.

 

Bronze concealed window lock assembly with mounting screws, shown on a white background.

Left-Hand Concealed Lock (1995 to 1998)

A‑Series or 400 Series sash lock assembly shown on a white background.

Left-Hand Concealed Lock (1999 to Present)

Safety Warning

A warning label that reads: Follow manufacturers' instructions for hand or power tools. Always wear safety glasses. Failure to do so may result in injury and/or product damage.

Tools and Supplies Needed

  • Safety glasses
  • Screwdriver
  • Pry bar
  • Utility knife
  • Hammer
  • 4d finishing nails
  • Cutting nippers
  • Wood filler

Let's Get Started

1. Order Parts

If your window was manufactured between 1995 and Present, order the applicable replacement sash lock Opens in a New Browser Tab for your window's series and manufacturing year online from the Andersen Parts Store.

 

Note: You need to know your window's handing to order the correct part. For assistance with determining your window's handing, see Casement Window Unit and Replacement Part Handing or Awning Window and Replacement Part Handing.

 

2. Install Parts

To install a replacement lock on Andersen A-Series and 400 Series casement or awning windows, use the written instructions or the YouTube® videos below.

 

  1. Open the window sash (the glass and framing around it) and remove the lock handle, lock bezel, operator handle, and operator cover from the window unit.
  2. Save the screws.
  3. Using a utility knife, score along the edge between the interior side stops and the frame to break the paint or stain seal (see image to the right). Be careful not to damage stops or extension jambs.
  4. Slide the flat end of the pry bar under the interior side stops to loosen.
  5. Remove interior side stops.
  6. Using the cutting nippers, remove any nails that may remain in the extension jambs and stops.
  7. Pull the nails from the backside of the stops to prevent damage to the face of the wood.
  8. Discard the nails.
  9. Remove the three (3) mounting screws from the lower sash lock and (if applicable) the two (2) mounting screws from the upper lock.
  10. Install the replacement sash lock using the original mounting screws or the screws provided with the replacement lock.
  11. Reapply the interior sash stops with 4d finishing nails.
  12. Fill nail holes with wood filler.
  13. Reinstall the lock handle, lock bezel, operator handle, and operator cover.
  14. Close the window sash and check the lock operation.

image.png

Interior Side Stops on the Frame

     

    Replace Casement Window Locks

     

    Note: This video will not apply to windows manufactured between 1995 and 1998.

     

    Replacing Locks on 400 Series Awning Windows

     

     

    © 2026 Andersen Corporation. All rights reserved.

     
    Replace-Lock-on-A-Series-and-400-Series-Casement-or-Awning-Windows
    Powered by