Why is my thermador freezer forming ice on top inside

The formation of ice on the top inside of your Thermador freezer could be due to several possible reasons: 1. Warm Air Leakage: If warm air is leaking into the freezer, it can condense and freeze on the coldest surfaces, such as the top inside. Check the freezer door gaskets for any damage or gaps that could be allowing warm air to enter. 2. Improper Door Sealing: If the freezer door is not sealing properly when closed, it can lead to cold air escaping and warm air entering the freezer, resulting in ice formation. Ensure that the door is closing tightly and that nothing is obstructing its proper closure. 3. Frost-Free System Malfunction: If your Thermador freezer has a frost-free system, which is designed to prevent ice buildup, a malfunction in the system can cause ice to form. Check the defrost system, including the defrost heater, defrost thermostat, and defrost timer, for any issues. 4. Temperature Setting: If the freezer temperature is set too low, it can lead to excessive frost and ice formation. Ensure that the temperature is set to the recommended level. 5. Air Circulation: Blocked or restricted air circulation inside the freezer can lead to uneven cooling and ice buildup. Avoid over-packing the freezer and ensure that air vents are not blocked. 6. Defective Door Heater: Some freezers have door heaters to prevent ice formation around the door gaskets. If the door heater is not functioning correctly, ice may accumulate on the top inside of the freezer. If you have tried troubleshooting the above issues and the ice formation persists, it is best to contact Thermador customer support or a qualified appliance technician for further inspection and repair. They can diagnose the specific cause of the ice formation and provide the necessary solutions to resolve the problem in your Thermador freezer.