High Lockout
8.E on Worcester Bosch Greenstar CDi Compact

Your boiler's internal memory has encountered an error and has reverted to its factory default settings, meaning it needs reconfiguring to work with your heating system.

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

Reset all parameters

What causes this fault?

This fault occurs when the boiler's internal computer suffers a data corruption or a temporary power fluctuation that wipes its stored memory. Effectively, the boiler has forgotten how to communicate with your specific heating setup and has reverted to its original factory settings for safety. The most common reason is a failing primary circuit board or a loose connection with the small 'code plug' that stores the unit's identity.

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

E5View →E9View →EAView →

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