Low
Fault Condition 11 on Worcester Bosch Greenstar 25i (ZWB 7-25)

Your boiler is displaying a status that typically indicates the appliance is in a standard standby or operating mode rather than a fault, meaning it is working exactly as it should.

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

Operating Instructions Quick Reference

Engineer required

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

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