Miele Refrigerator Error Code F3 — Evaporator Sensor Fault
What this means
Error F3 on Miele refrigerators indicates the evaporator NTC sensor is faulty. This sensor monitors the evaporator coil temperature to control defrost cycles and fan operation. If it fails, the automatic defrost system may not work properly, leading to ice buildup on the evaporator, reduced cooling, and eventually a warm fridge and/or freezer.
Alternate codes: F 3, F03
Step-by-step fix
4 stepsCheck for ice buildup
Open the fridge/freezer and remove the back panel inside to expose the evaporator. If there is heavy ice buildup on the evaporator coils, the defrost system has been failing — likely because this sensor was not reporting correctly.
Heavy frost is a strong indicator that the evaporator sensor failed some time ago, not just recently.
Defrost manually if needed
If ice is present, unplug the refrigerator and let it defrost naturally with the doors open (place towels to catch water). Or use a hairdryer on low heat to speed up the process. Do not use sharp tools to remove ice.
Full defrost may take 4–8 hours. Transfer perishable food to a cooler with ice.
Test the evaporator sensor
Once defrosted, locate the sensor on or near the evaporator coil. Disconnect and test resistance. At room temperature, it should read approximately 5 kΩ (for a standard NTC). If frozen in ice, wait until it thaws before testing.
The sensor wire may be frozen into the ice block — defrost completely before attempting to remove it.
Replace the sensor and reassemble
If the sensor is faulty, replace it. Clip or mount the new sensor in the same position on the evaporator. Reassemble the cover panel, close the doors, and plug in.
After replacing the sensor, monitor the fridge for 2–3 days to ensure it defrosts normally and no ice re-accumulates.
When to call a professional
If ice buildup is severe and recurring despite a new sensor, the defrost heater, defrost timer/board, or the main control board may also be faulty.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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