Low
Er08+ on Biasi Activa

Your boiler's outside temperature sensor has developed a fault or is sending incorrect data, which might stop the heating from adjusting correctly to the weather.

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

Faulty external temperature probe NTC (if fitted)

Engineer required

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

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