F21Serious
Samsung Oven/Range F21 Error Code
The oven temperature sensor circuit is open (disconnected or broken).
Common causes
- Faulty oven temperature sensor
- Loose or broken wiring to sensor
- Damaged connector
How to fix it
- Unplug the range and let it cool completely.
- Access the oven temperature sensor inside the oven cavity (usually at the back wall).
- Check the sensor connector for secure attachment and inspect wires for damage.
- Measure sensor resistance with a multimeter (should be ~1090 ohms at room temp).
- If resistance is out of range or open, replace the sensor.
⚠ When to call a pro: If the sensor checks good but code persists, the control board may be faulty; call a technician.
Part links are affiliate links — as an Amazon Associate we may earn a small commission at no extra cost to you.
Always unplug the appliance (and turn off the water for washers/dishwashers) before inspecting. These guides are for information only and are not a substitute for a professional repair.