Medium
E15 on Alpha CD28

Your boiler's temperature sensors have been swapped over, meaning it cannot correctly measure the heat of the water circulating through your system.

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

Flow and return NTCs transposed

Engineer required

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

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E14View →

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