c21Serious
Frigidaire Dishwasher c21 Error Code
The water temperature inside the dishwasher has exceeded safe limits. The heating element may be faulty.
Common causes
- Defective thermistor or temperature sensor
- Stuck heating relay on control board
- Malfunctioning control board
How to fix it
- Unplug dishwasher for 15 minutes to reset.
- Check if heater element is on constantly (if visible).
- Ensure water inlet temperature is not excessively hot.
⚠ When to call a pro: If error returns, call a pro to test thermistor and control board; risk of fire or damage.
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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.