High Lockout
Fault 02 / 205 on Worcester Bosch Greenstar CDi Compact

Your boiler's internal memory has encountered a glitch, causing some of its important settings to reset themselves to the factory defaults.

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

Internal fault: Some parameters reset to factory settings due to EEPROM problem. Some parameters reset to default.

What causes this fault?

This fault occurs when the boiler's internal memory chip, or EEPROM, fails to communicate correctly with the main control board. It is typically caused by a minor electrical surge or hardware degradation that corrupts the stored configuration data. As a result, the boiler loses its specific operating instructions and defaults to factory settings as a safety precaution.

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 →F0View →

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