Low
Err.1 on Atag Q 25S

Your boiler has recorded a previous fault in its history log, which acts as a memory of a past issue rather than a sign of a current active breakdown.

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

1st last predecessing error

Engineer required

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

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Related fault codes

Err.2View →Err.3View →

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