Error Code E20 / F20

Washing Machine Error Code E20 / F20 (Bosch, Siemens, Neff, Constructa)

Definition of the Error

The error codes E20 or F20 indicate a critical malfunction within the appliance’s heating system. Specifically, the machine has detected an unexpected temperature issue, such as:

1. Heating failure: The required water temperature was not reached within the expected cycle time.
2. Temperature Sensor (NTC) malfunction: The appliance is receiving inaccurate or no temperature readings from the sensor, preventing effective heat regulation.

This fault typically causes the washing program to halt immediately or continue running indefinitely without advancing past the heating segment of the cycle.

Common Causes for E20 / F20

The E20 / F20 error points primarily to hardware components responsible for heating the wash water:

• Faulty Heating Element (Heater): The heating element may have burned out, shorted, or developed excessive scaling, preventing it from raising the water temperature efficiently.
• Malfunctioning NTC Temperature Sensor: The Negative Temperature Coefficient (NTC) sensor monitors the water temperature and provides feedback to the main control board. If this sensor is damaged, disconnected, or reads incorrectly, the machine cannot determine when to switch the heater on or off, resulting in the error code.
• Wiring and Connection Issues: A loose, corroded, or damaged wire connection between the main control board and either the heating element or the NTC sensor can interrupt the circuit and trigger the fault.
• Main Control Board (PCB) Failure: Although less common, the module that controls the power relay for the heating circuit may have failed.

Initial Troubleshooting Steps (User Actions)

Before contacting technical support, perform these simple checks and resets:

1. Power Reset Cycle

A temporary electronic glitch can sometimes trigger this error. Performing a hard reset may clear the code:

• Unplug the washing machine completely from the power outlet.
• Wait for at least 5 to 10 minutes to allow any residual charge in the control board capacitors to dissipate.
• Plug the appliance back in and attempt to run a short test cycle (e.g., Rinse/Spin or a short Quick Wash program) to see if the error persists.

2. Check Electrical Supply

Since heating elements draw significant power, ensure the circuit breaker has not tripped due to the load:

• Verify that the main circuit breaker associated with the washing machine’s outlet has not switched off. If it has, reset the breaker and observe if the fault returns immediately. Persistent tripping is a sign of a severe electrical short in the heating circuit, requiring immediate professional attention.

3. Run a Program Without Laundry

Run a brief wash program (e.g., 40°C or 60°C) without any laundry or detergent. This isolates the error to the heating system itself and ensures external factors (like an overloaded drum) are not contributing to cycle delays interpreted as a fault. If the machine completes this cycle, the error might have been intermittent.

When to Contact Professional Service

If the error code E20 / F20 returns immediately after a reset, or if the initial troubleshooting steps fail to resolve the issue, the problem involves internal electrical components that require specialized tools and knowledge.

Do not attempt to replace the heating element or sensor yourself unless you are a qualified technician. These procedures involve accessing high-voltage components and water seals.

A service technician will need to perform the following diagnostics:

• Test the Resistance: Measure the continuity and resistance (Ohms) of the heating element to confirm it is intact.
• Verify Sensor Values: Test the resistance of the NTC temperature sensor to check if its measured temperature corresponds to the actual water temperature.
• Inspect Wiring Harness: Visually and physically inspect the wires leading to the heater and sensor for signs of corrosion or breakage.