High
2946 V on Worcester Bosch Junior 28i

Your boiler's internal computer chip is failing to communicate correctly, meaning the system doesn't know which model it is and has stopped working for safety.

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

Incorrect code plug detected – the code plug needs replacing

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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