High
2957 on Worcester Bosch Greenstar 2000

Your boiler's internal computer is experiencing a software glitch or communication error that is preventing the burner from igniting 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

Hydraulic configuration at the heat exchanger activated

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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