How much does it cost to fix Alpha error code C2?

Typical repair cost for the Alpha C2 fault is £120-200 including labour.

C2 High

Alpha C2 Fault Code

Q: What does the Alpha C2 fault code mean?

Your boiler has stopped working because a sensor that monitors the water temperature inside your heating system is giving incorrect or no information to the control board.

The Alpha C2 fault code means: your boiler has stopped working because a sensor that monitors the water temperature inside your heating system is giving incorrect or no information to the control board.. It appears on 2 Alpha models in our database.

Technical description: Primary flow temperature sensor faulty (no heating)

Typical repair cost £120-200 (including labour)

Engineer required

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

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Alpha models that show the C2 fault code

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

Cd13r Repair: £120-200
CD24 Repair: £90-160

Source

Alpha C2 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

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