Medium
Er 12 on Biasi Advance 25C

Your boiler has sensed a problem with the internal sensor that monitors the temperature of the water returning from your radiators.

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

Faulty central heating temp. probe NTC (return)

Engineer required

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

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Related fault codes

Er 05View →Er 11View →Er 14View →

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