Whirlpool Cooktop Error Code F-21 E-00

F-21 E-00 indicates a supply power frequency error detected by the power control board, classified as a Type 2 failure. This means the board cannot correctly read or process the incoming AC line frequency. As a result, all burners connected to that power control board are disabled. The power control board requires replacement to resolve this fault.

A power reset will not permanently clear F-21 E-00 because the fault reflects an internal hardware failure in the power control board's frequency detection circuitry. The code will return as soon as the cooktop powers back on and the board attempts to read the supply frequency. Board replacement is the required fix.

Repair costs vary depending on the specific cooktop model and whether you hire a technician or do the repair yourself. A replacement power control board typically ranges from roughly $100 to $300 or more depending on the model, and professional labor can add another $75 to $200. Getting a parts quote for your specific model number before committing to the repair is recommended.

The repair requires disconnecting power to the cooktop and replacing the power control board. A knowledgeable DIYer who is comfortable working with appliance electronics and following safe lockout procedures can perform this repair. However, because cooktops involve high-voltage components, anyone unfamiliar with electrical safety should hire a qualified appliance technician.

The F-21 E-00 fault disables all burners on the affected power control board, so the cooktop will not operate normally. Do not attempt to bypass the fault or continue using the appliance in this condition. Disconnect power and arrange for the power control board to be replaced before resuming use.