13 High

Atag 13 Fault Code

The Atag 13 fault code means: your boiler has experienced an internal computer error that is preventing it from starting up correctly.. It appears on 1 Atag model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Internal error
Typical repair cost £250-500 (including labour)

DIY fix possible

Locate the Reset button on the control panelPress and hold the Reset button for 2-3 secondsWait for the boiler to complete its restart sequence

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Atag models that show the 13 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Atag 13 fault code information on this page is sourced and cross-checked against the official Atag service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026