High
2946 on Worcester Bosch Greenstar 4000

Your boiler's internal computer chip has identified that the plug-in electronic key is either missing, faulty, or doesn't match the specific model of your boiler.

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

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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