High
C2 on Alpha Cd13r

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Primary flow temperature sensor faulty (no heating)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

C1View →

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