Low
46 on Alpha Eco

Your boiler has lost the connection to an optional external temperature sensor, which usually means a wire has come loose or the sensor has been disconnected.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

No continuity of external sensor circuit

Engineer required

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

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