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Green/Red - blinking on Worcester Bosch Greenstar 27CDi

Your boiler is notifying you that it is currently running, but it has detected a minor inconsistency in how it is circulating water around your system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Warning mode (pump operating in an abnormal condition, no risk for the pump functionality).

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E9View →

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