Ariston Washer Error Code F3

The F3 code on an Ariston washer indicates that the water temperature NTC thermistor is either open or shorted. This sensor monitors water temperature throughout the wash cycle, and the control board has detected that its resistance reading is outside the acceptable range. The washer stops operation to prevent unsafe heating conditions. Both a broken thermistor and a wiring fault can trigger this code.

No, you should not continue running the washer while F3 is active. Without a functioning temperature sensor, the control board cannot accurately regulate the heating element, which creates a risk of overheating the water or the appliance. Stop using the machine until the fault is diagnosed and repaired.

A reset may temporarily clear the F3 code, but if the underlying fault with the NTC thermistor or its wiring is still present, the error will return once the washer attempts to run a cycle that involves temperature monitoring. A reset is useful for confirming whether the fault is intermittent, but it does not repair the root cause. The wiring and thermistor should be properly diagnosed and repaired for a lasting fix.

A knowledgeable DIYer can start by checking the wiring harness and connector between the NTC thermistor and the control board for visible damage, corrosion, or loose connections, and test continuity with a multimeter. If the wiring is intact, the thermistor itself can be tested for correct resistance and replaced if faulty. However, if the control board is suspect, professional diagnosis is recommended before purchasing that component.

If the fix is simply reseating a connector or repairing a wiring harness, costs can be minimal, primarily covering a service call in the range of $75 to $150. Replacing the NTC thermistor is typically an inexpensive part, with total repair costs often ranging from $100 to $200 including labor. A control board replacement, if needed, can raise the total cost to $200 to $400 or more depending on parts availability and labor rates.