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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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Greenstar_2000_installation_instructions installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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