Excessive frost buildup on shelves, walls, and food items inside the freezer.

Safety first: Unplug the freezer before defrosting or inspecting gaskets.

• Inspect gasket: Check for tears, gaps, or hardened sections. Clean the gasket and mating surfaces with warm soapy water and dry thoroughly.
• Check door alignment: Ensure the door is level and square. Adjust hinges if the door is sagging and not contacting the gasket evenly.
• Defrost manually: Remove food to a cooler, unplug the freezer, and leave the door open until all frost melts. Use towels to catch water; do not chip ice with sharp tools.
• Evaluate usage: Reduce door openings and avoid placing hot or uncovered moist food inside, which increases humidity.
• Check defrost system: If frost quickly returns on the rear panel, inspect defrost heater, thermostat, and sensor as in E4/E10.

Persistent heavy frost despite good sealing and normal defrost operation may indicate cabinet or liner damage; consult a technician.