Fisher & Paykel Dishwasher Error Code F3

The F3 error code on a Fisher & Paykel dishwasher indicates that the control electronics have detected a water temperature exceeding 80°C within the wash system. The dishwasher continuously monitors water temperature through a dedicated temperature sensor, and when the sensed value crosses this 80°C threshold, the machine triggers the F3 fault to prevent damage to internal components, dishes, or potential safety hazards. The temperature monitoring circuit feeds sensor data through an analog-to-digital converter (ADC) on the control board, which translates the raw signal into a readable temperature value.

There are four primary failure paths that lead to this code. First, the heating element may have failed in a shorted or continuously energized state, causing it to heat water beyond the normal operating range without proper control. Second, the temperature sensor itself may have drifted or failed, producing a falsely elevated resistance reading that the ADC interprets as excessive heat. Third, the ADC circuit on the electronics board may have failed internally, corrupting the temperature signal regardless of actual water conditions. Fourth, and the first item to rule out during diagnostics, the incoming hot water supply to the dishwasher may simply be arriving at a temperature above 80°C due to a water heater set too high.

Diagnosing F3 correctly requires working through each of these failure modes in order of accessibility. Start by verifying the incoming water temperature at the supply line using a thermometer. If the supply temperature is within normal range, the fault points to one of the three internal component failures: the sensor, the heating element, or the control board ADC. Sensor and element testing typically involves resistance checks with a multimeter, while ADC failure on the board is usually confirmed by exclusion after the other components test within specification.