Error Code 21C
Freezer evaporator fan is not running when it should be
Moderate
Address soon - your appliance may not work properly
Also displayed as: 21C
What This Means
Feedback signal wire loose or broken at CN20; Fan motor winding open or short; Fan blade obstructed by ice or foreign object; Loss of 7V–12V supply to fan motor
What actually causes this:
The fan that circulates cold air through the freezer has stopped due to a failed motor, wiring problem, or ice blocking the blades.
First Thing to Check
Open the freezer, listen for the fan — if it is silent while the compressor is running, check if ice has built up around the fan blades.
Parts Involved
How to Fix
- 1
Enter forced operation mode and check if fan runs
- 2
Measure voltage between Main PCB CN20 PIN 16 and PIN 18; should be DC 7V–12V
- 3
Check pulse signal at CN20 PIN 14 when fan is spinning
- 4
Verify door switches are properly closed (open door disables fan)
- 5
Check for ice buildup blocking fan blades
- 6
Replace fan motor if supply voltage is correct but motor does not spin
This Error Applies To
Samsung DRF36C Series Refrigerators (2022) (2022–present)
Related Error Codes
Internal I/O expander chip on main board has a communication fault
Freezer temperature sensor is disconnected or out of range
Freezer defrost sensor is disconnected or reading out of range
Condenser fan motor in the machine compartment is not running
External temperature sensor is unplugged or has failed
Freezer defrost heater or safety cutout has failed or wiring is open
Fridge temperature sensor is disconnected or out of range
Humidity sensor is disconnected or out of range