High
C14 on Atag Premier

Your boiler has detected that the water trap responsible for disposing of condensation is potentially blocked or not draining correctly, causing it to shut down to prevent internal water damage.

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

Siphon sensor fault

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

C15View →

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