Error Code 21
Freezer fan is not spinning
Critical
Stop using immediately - risk of damage or safety issue
Also displayed as: 21C
What This Means
Fan connector not properly connected at Main PCB CN74 pins 1-4; Fan motor wire damaged or broken; Fan motor defective (bearing seized or motor failed); Main PCB defective or fan relay faulty
What actually causes this:
Fan motor failed or ice is blocking the fan blades
First Thing to Check
Check if freezer is getting cold — if not, the fan has likely stopped working
Parts Involved
How to Fix
- 1
1. Unplug refrigerator and inspect CN74 connector pins 1-4
- 2
2. Check for loose or corroded connections
- 3
3. Reseat connector firmly
- 4
4. Power on and listen for fan operation
- 5
5. If fan doesn't run, measure voltage at CN74-1 to CN74-3 — normal 7V to 12V
- 6
6. If voltage is normal but fan doesn't run, fan motor is defective
- 7
7. If voltage is abnormal, check Main PCB relay circuit
This Error Applies To
Samsung RF22N9781 Series Refrigerators (2018) (2018–present)
Related Error Codes
Freezer temperature sensor malfunction
Room temperature sensor not working
Ice maker temperature sensor failure
Fridge temperature sensor is not responding
Convertible zone temperature sensor failure
Ice storage area temperature sensor malfunction
Freezer defrost sensor is faulty
Convertible zone defrost sensor malfunction