This article will help you identify the type of glass used in your Andersen® windows and patio doors. You'll find sample images of common glass codes to guide you through the process.

Locate Andersen® Glass Logo

Start by locating the Andersen® logo, which is etched directly onto the glass surface. It's usually found in one (1) of the lower corners of the window or patio door. If the etching is hard to read, try these tips to make it more visible:

The Andersen® logo is etched directly onto the glass surface, typically positioned in one (1) of the lower corners. If the etching is faint or hard to see, try these simple tips to improve visibility:

• Use a magnifying glass to enhance small details
• Take a digital photo and zoom in on the image
• Shine a flashlight across the glass to highlight the etching
• Hold a dark piece of paper behind the glass to reduce glare and improve contrast

Identify Glass Type

Around the Andersen glass logo will be a series of letters and numbers indicating the glass type. This notation varies based on the selected glass type and may include, but is not limited to, HP Low-E, High-Performance (HP), HP Sun, HP Smart Sun, Dual-Pane Clear, etc. The Andersen® logo does not always specify the specialty glass in the window or patio door. Tinted or patterned glass types will not be marked.

Additional logo examples can be seen in Glass Types .

Example of a Glass Code

Tempering Code

Depending on the window or patio door type, the unit may have a tempering code etched into the glass surface. The tempering code does not identify the glass type. Please locate the Andersen® logo to determine the glass type.

Tempered Glass Code

FX-Number

Since 2002 Andersen has etched FX-Numbers directly onto the glass of Flexiframe®, Arch and Springline™ units for easy identification. However, Monolithic Impact-Resistant Glass does not include an FX-Number etching.

If your window or patio door was manufactured before 2002, the FX-Number might be located in a different spot, such as under the sill stop or printed on the glass label. For help locating and reading your product label, review our Identify Your Andersen® Window or Patio Door Using a Product ID Label article.

Example of a FX-Number on the Sill Stop

Example FX Order Number

Contact Andersen® Windows and Doors if unsure about the glass type or where to find the Andersen® logo.

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