⚠️ Safety Warning: Appliance repair involves electricity, gas, and moving parts. Always disconnect power before working on any appliance.
Error Code: F21 Difficulty: Hard
Problem: Water softener error.
How to Fix F21 Error (Step-by-Step)
- Begin by completely disconnecting the dishwasher from power by turning it off at the circuit breaker for at least 5-10 minutes. This allows the internal electronics to fully reset.
- Restore power to the dishwasher at the circuit breaker and confirm the error stays cleared during a full test cycle.
- For some models, this error requires entering a special check mode to clear. To do this, press and hold the ‘Rinse Only’ and ‘Delay Start’ buttons simultaneously for about 5 seconds, or until the panel lights change, indicating you have entered the service menu.
- Once in check mode, do not press any other buttons for at least one minute. The dishwasher will perform a self-check, which can help clear internal communication errors related to the water softener system.
- To finalize the reset and clear the code from memory, press the ‘Start/Cancel’ button for 3-5 seconds until the dishwasher drains and resets.
- Exit the check mode by pressing the main ‘Power’ button. If the error is cleared, the normal cycle selection should appear.
- Turn the appliance off, wait about 2 minutes, then turn it back on.
Parts Availability Note: For this Electrolux/Frigidaire error code, exact OEM part numbers can vary by model revision and serial range. We’ve listed the most likely component(s), but confirm compatibility using your full model number before ordering. If no exact SKU is shown, use this guide for diagnosis first, then verify the matching OEM part on RepairClinic or PartSelect.
Still Not Working?
If the replacement part didn’t fix the issue, you may have a wiring problem or main board failure.
Most DIY parts are $50–$250. If you have a quote, use the total.
More options (for a better recommendation)
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Expert: Mike Sullivan
EPA Section 608 Certified Technician with 18+ years experience.
Read Editorial Standards →Browse all Electrolux error codes: Electrolux Error Codes
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