High
Poor performance / noises on Worcester Bosch Greenstar i

Your boiler is struggling to breathe or burn gas correctly, which is causing unusual sounds and preventing it from heating your home efficiently.

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

Fan / fan harness. Sensors not fixed or out of specification. Gas pressure / blockage. Water pressure / blockage. CO2 mix. Flue blockage.

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

C6View →E9View →EAView →

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