Fisher & Paykel Cooktop Error Code F3

The F3 error code on a Fisher & Paykel cooktop indicates a temperature fault originating from the burner thermistor. The thermistor is a resistive temperature sensor mounted on the burner board that continuously monitors heat levels at the burner. When the cooktop's control system reads a temperature value outside the acceptable operating range, specifically above 221°F (105°C) or below -22°F (-30°C), it interprets this as a fault condition and displays F3. A reading at either extreme typically points to a thermistor that has failed open or shorted rather than an actual temperature condition at those limits.

The burner board thermistor works by changing its electrical resistance in proportion to temperature. The control board converts this resistance reading into a temperature value. If the thermistor circuit is broken, the board may read an impossibly low resistance or infinite resistance, producing a temperature value that falls outside the defined limits. Physical damage to the thermistor, corrosion at the connector pins, or a cracked thermistor body are the most common failure modes. Wiring harness damage between the thermistor and the burner board can produce the same out-of-range signal.

Diagnosing F3 begins at the burner board thermistor itself. A technician should inspect the thermistor and its connector for visible damage, then use a multimeter to check the resistance value and compare it against the expected range for the ambient temperature. If resistance reads open or near zero, the thermistor has failed and requires replacement. If the thermistor reads correctly, attention should shift to the wiring harness and connector integrity, and then to the burner board itself.