On the covered Samsung range or oven, C-20, C-21, E-21 means the oven temperature-sensor signal is invalid or out of range. First, turn the oven off and allow complete cooldown. Then: arrange sensor/wiring service. Do not use the oven again until the sensor or its wiring has been serviced.
Try in this order
0 of 3 completedWhat to do first
ReversibleTurn the oven off and allow complete cooldown.
Correct only the documented fault domain
ReversibleArrange sensor/wiring service.
Have the sensor measured
ReversibleA Samsung oven temperature sensor reads about 1,080 ohms at room temperature (25 C). Service notes treat more than about 2,950 ohms as an open sensor and less than about 930 as a short, and a normal reading then points at the control board.
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Common questions about “Samsung range or oven code C-20, C-21, E-21”
What does C-20, C-21, E-21 mean on a Samsung range or oven?+
The oven temperature-sensor signal is invalid or out of range.
How much does a Samsung oven temperature sensor cost?+
It is an inexpensive part compared with a control board, which is why it is tested and replaced first when it reads out of range.
Does C-20 or C-21 mean the oven is too hot or too cold?+
Neither: it means the control cannot trust the temperature reading, so the sensor circuit is checked instead of the element or the thermostat setting.