High
259 on Worcester Bosch Greenstar 8000 Style

Your boiler has detected an internal communication error with its main control system, meaning it cannot process the signals needed to operate safely.

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

Heat demand lower than energy supplied

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

2961View →2962View →

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