How much does it cost to fix Atag error code C1 10?

Typical repair cost for the Atag C1 10 fault is £150-300 including labour.

C1 10 High

Atag C1 10 Fault Code

Q: What does the Atag C1 10 fault code mean?

Your boiler has detected that it is running much hotter than it should be and has automatically switched itself off to prevent damage.

Also written as C110 — same fault.

The Atag C1 10 fault code means: your boiler has detected that it is running much hotter than it should be and has automatically switched itself off to prevent damage.. It appears on 4 Atag models in our database.

Technical description: Safety temperature exceeded

Typical repair cost £150-300 (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 C1 10 fault code

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

A200 Repair: £150-300
Q 25CR Repair: £150-300
S 25CR Repair: £150-300
Sov. Repair: £120-350

Source

Atag C1 10 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