Low
00h - FFh on Worcester Bosch Greenstar 25i (ZWB 7-25)

Your boiler is currently running through its normal internal health check or diagnostic display mode and is not currently reporting a specific malfunction.

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

GFA status / error display range

Engineer required

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

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