High
242 to 256 / F0 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected an internal computer error that prevents it from starting safely.

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 error call Bosch help line 0330 123 3366

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

F0View →

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