Medium
8 + on Biasi Antares Combi

Your boiler's outside temperature sensor has failed, meaning the system doesn't know how hard it needs to work to heat your home based on the weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

External NTC probe failure.

Engineer required

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

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