How much does it cost to fix Atag error code A2?

Typical repair cost for the Atag A2 fault is £150-250 including labour.

A2 High

Atag A2 Fault Code

Q: What does the Atag A2 fault code mean?

Your boiler has detected that the water it is trying to heat is reaching a dangerously high temperature, so it has shut itself off to stay safe.

The Atag A2 fault code means: your boiler has detected that the water it is trying to heat is reaching a dangerously high temperature, so it has shut itself off to stay safe.. It appears on 2 Atag models in our database.

Technical description: Hot water temperature

Typical repair cost £150-250 (including labour)

Engineer required

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

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Atag models that show the A2 fault code

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

A200 Repair: £120-250
Q 25CR Repair: £150-250

Source

Atag A2 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