High
46 on Alpha E-Tec Plus 28

Your boiler has stopped working because a safety link that tells the unit it is safe to operate has been disconnected or triggered.

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

Optional external safety sensor intervention - No continuity on external sensor circuit. Check link is present in external connections 14 and 15 or if fitted external safety device has activated

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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