Miele Refrigerator Error Code F5 — Defrost System Fault
What this means
Error F5 on Miele refrigerators indicates the defrost system has failed. Modern frost-free refrigerators periodically heat the evaporator to melt accumulated frost. If the defrost heater does not work, the defrost thermostat is faulty, or the control board does not initiate defrost cycles, ice accumulates on the evaporator and eventually blocks airflow, leading to warm temperatures in the fridge and/or freezer.
Alternate codes: F 5, F05
Step-by-step fix
4 stepsCheck for ice buildup on the evaporator
Remove the back panel inside the freezer compartment to expose the evaporator. If the evaporator is heavily iced, the defrost system has not been running properly.
A thin layer of frost is normal. A thick ice sheet covering the entire evaporator is not.
Manually defrost
Unplug the refrigerator and allow the ice to melt. Use towels to catch the water. This may take 4–8 hours for a full defrost.
You can speed up defrosting with a hairdryer on low heat, but keep the dryer moving and do not concentrate heat on plastic parts.
Test the defrost heater
With the ice melted and the unit unplugged, locate the defrost heater (a glass tube or coiled element mounted on or near the evaporator). Disconnect it and test for continuity. A good heater shows a measurable resistance (typically 20–80 ohms). Open-circuit means it has burned out.
Also check the defrost thermostat (bi-metal) — it should be closed (continuity) at room temperature and open at high temperatures.
Replace the faulty component
Replace the defrost heater if it is open-circuit, or the defrost thermostat if it does not switch properly. Reassemble the evaporator panel, plug in, and monitor over the next few days.
If both the heater and thermostat test fine, the control board may not be initiating defrost cycles — this requires professional diagnosis.
When to call a professional
If the heater and thermostat are fine but ice continues to build up, the control board's defrost timer/control circuit has failed and needs professional replacement.
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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