Condensation or fogging on the glass door, especially in humid environments.

Safety: Unplug before testing heater circuits.

• Check environment: High humidity rooms will cause some condensation. Use a dehumidifier or improve ventilation.
• Inspect gasket: Replace the door gasket if it is not sealing properly.
• Test door frame heater: If equipped, measure resistance of the door frame heater. Replace if open.
• Usage habits: Reduce frequency and duration of door openings to limit moisture entry.