High
2946 on Worcester Bosch Greenstar 4000 System

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.

What the manual says

Manufacturer manual

Incorrect code plug detected

Shared across the Greenstar 4000 range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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All 105 fault codes on the Greenstar 4000 System

Seeing a different code? Every code this model can display, in one place.

20020120220320420821422422722823223323423523723824224524925025125225325425825926226326526826927328128328430530635335735836036236381081110101013101710181019102110221023103710651068107010711072107310741075107620852908291029142915291629202923292729282931294029482949295029512951 V29522952 V29572957 V29612961 V29622962 V29632963 B29642964 B29652965 B29662966 B29672967 B29702970 B29712971 B29722972 V

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