If the head or sill plugs on your 400 Series gliding windows are damaged or missing, you will want to replace them. Replacing head and sill stops in 400 Series gliding windows can be done in a few quick and easy steps.

How to Replace Andersen® Head and Sill Plugs

Outside air may begin to come into your home if the head or sill plugs are missing. The head plug is located at the top of the frame, where the two (2) window sashes meet. The sill plug is located at the bottom of the frame, where the two (2) window sashes meet. This article provides step-by-step instructions to replace the head or sill plugs.

Universal Head and Sill Plug for 400 Series Gliding Windows

This Article Will Help You:

• Replace head or sill plugs.

Safety Warning

Tools and Supplies Needed

• One (1) soft cleaning cloth
• Safety glasses
• Mild soapy water
• Andersen® Installation Sealant
• Needle-nose pliers
• Replacement head or sill plug

Let's Get Started

Replace Head or Sill Plugs

1. Remove the window sash following steps one (1) through four (4) on Page 2 through Page 4 in the Window Sash Replacement Guide (0004368).
2. Using needle nose pliers, pry the original head or sill plug from the frame.
3. Clean the area with mild soapy water and a soft, dry cloth to remove any dirt or debris.
4. Apply an amount of installation sealant that is slightly smaller than the base of the head/sill plug in the window frame where the original plug was located.
5. Firmly press the new plug into the installation sealant until set.
6. Reinstall the window sash following steps six (6) through seven (7) On Page 5 in the Window Sash Replacement Guide (0004368).

Need Parts?

Contact Andersen® Windows and Doors to properly diagnose a concern and order replacement head or sill plugs for your 400 Series gliding window. The replacement head or sill plugs are universal in size and color and will work for all 400 Series gliding windows.

Related Articles

For video instructions on how to remove and reinstall the window sash in Steps One (1) and Six (4) above, see Sash Replacement Instructions for 400 Series Gliding Windows. The article and video will walk you through replacing the entire sash, you will not follow those steps and focus only on replacing head or sill plugs.

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