High
1-E3 on Worcester Bosch Greenstar 8000 Life System

Your boiler is having trouble 'reading' its internal settings because a small plug that tells the computer how to operate the system has become loose or faulty.

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

Code plug number Coding plug number.

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

1-E4View →

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