1. Locate 2 screws at the base of plastic duct that covers fan in freezer
2. Use a Phillips head screwdriver to remove the two screws, and set them aside
3. Carefully slide the duct up toward the top of the freezer (for top-freezer units) and remove by pulling toward freezer door once it is free of the brackets holding it in place. This will expose the duct foam.
4. Lift duct foam from the duct
5. Place new duct foam in the duct
6. Carefully replace the plastic duct. It should be firmly attached to the brackets in the back of the freezer, and also cover the duct foam completely. Do not use too much force, as it may damage the new foam.
7. Use the Phillips head screw driver to replace the two screws
8. Check to make sure that the plastic duct is flush with the freezer, so that the air is directed correctly.