High
EC 256 on Worcester Bosch 26 CDi Xtra

Your boiler’s internal computer has encountered a critical error and has stopped the heating process to ensure 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

The burner control unit has an error

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

EAView →E9View →

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