High Lockout
EE2 on Worcester Bosch WR325 RSF

Your boiler has detected that a temperature sensor is giving readings outside of its normal bounds, causing the system to shut down as a precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Sensor temperature limitations

What causes this fault?

This fault occurs when the main control board receives a signal from a temperature sensor that is far beyond the expected range, suggesting the component has failed or its connection is broken. It is usually caused by an internal short-circuit in the sensor or a loose wire in the harness that prevents the boiler from accurately monitoring heat levels. As a safety measure, the system stops firing to prevent potential overheating or damage to the heat exchanger.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

EAView →E2View →E9View →

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