The Whirlpool Duet Washer F05 Error is related to the water temperature sensor, also known as the NTC sensor. This error occurs when the sensor detects that the water temperature is not within the expected range during the wash cycle. If the sensor's resistance value falls outside the specified range, the washer's control board will stop the cycle and display the F05 error code.

This error is critical because it prevents the washer from operating correctly, ensuring that the water temperature is maintained at the optimal level for effective cleaning. Understanding the F05 error code is essential for diagnosing why your washer may have stopped mid-cycle.