The “Defrost Not Completed” error code indicates that the control board initiated a defrost cycle, but the evaporator temperature did not rise to the expected threshold within the allotted time. This suggests that something interrupted or shortened the defrost cycle, leaving ice on the coils and reducing the fridge’s cooling efficiency.
Common Causes
Several factors can cause an incomplete defrost cycle. The defrost heater may be taking too long to melt the ice due to excessive buildup, often caused by a previous defrost system failure. The thermal fuse may trip mid-cycle, cutting power to the heater. A partially failed heater element, which produces reduced output, can also prevent the coils from reaching the required temperature. Additionally, the defrost sensor may terminate the cycle too early, mistaking the coil temperature for a safe level.
Solutions
Perform a manual defrost by unplugging the fridge and allowing it to thaw completely for 24–48 hours. If cooling is restored afterward, the defrost system is likely failing progressively. Test all defrost components in sequence, including the heater, thermal fuse, thermostat, and sensor, to identify the faulty part. Check the defrost cycle timing on models with adjustable intervals; a cycle window that is too short may not allow enough time for the heater to complete its task. Inspect the freezer for unusually heavy ice buildup, which can indicate a door seal leak or excessive moisture entry.
Prevention Tips
To prevent incomplete defrost cycles, ensure the freezer door is always closed properly and that the gasket is in good condition. Regularly check the defrost system components for signs of wear or damage. Avoid overloading the freezer, as this can obstruct airflow and lead to excessive frost buildup.