Low
Fault Condition 11 on Worcester Bosch ZB 7 27 HE

Your boiler is signalling that it needs you to refer to the basic operation instructions because it is not currently running as expected.

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

DIY fix possible

Check that your hot water or heating controls are set to 'On'Ensure the boiler's mode selector dial is turned to the correct position for winter or summer usePress the reset button briefly to see if the boiler restarts

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