High
235 on Worcester Bosch Greenstar 27CDi

Your boiler's internal computer is confused because its internal identification settings do not match the specific components installed, causing it to lock itself to prevent incorrect operation.

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

Conflicting versions of boiler electr. and boiler identification

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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