Error Code 21
Freezer evaporator fan motor is not running or not responding
Critical
Stop using immediately - risk of damage or safety issue
Also displayed as: Error 21
What This Means
Freezer BLDC fan motor failed; No 7V-12V supply to fan motor; Pulse feedback wire damaged or disconnected; Foreign object (ice) blocking fan blades; Wiring harness to fan disconnected
What actually causes this:
The fan that circulates cold air through the freezer has stopped working, usually due to motor failure, ice blockage, or a wiring problem.
First Thing to Check
Listen for the freezer fan running — if silent, check for ice buildup around the fan blades by removing the freezer evaporator cover.
Parts Involved
How to Fix
- 1
Check voltage at MAIN PCB CN31-8 to CN31-9: should be DC 7V to 12V
- 2
Check pulse signal at CN31-7 to CN31-9: should alternate about 2-3V with multimeter
- 3
Run forced test from engineer mode to activate fan manually
- 4
Verify door switch operation (fan delays 7 minutes after door open/close)
This Error Applies To
Samsung RF23M85 Series Refrigerators (2017) (2017–present)
Related Error Codes
Mid drawer damper heater has an open or short circuit
Refrigerator defrost sensor has failed or disconnected
Freezer defrost sensor has failed or lost connection
Freezer temperature sensor has failed or lost connection
Ambient room temperature sensor has failed
Refrigerator compartment temperature sensor has failed or disconnected
Flex Zone (middle drawer) temperature sensor has failed
Humidity sensor in the fridge compartment has failed