Low
C123 on Atag Q 30CR

Your boiler is currently locked in an installer-only restricted menu that prevents normal operation.

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

Installer level access code

Engineer required

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

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