Medium
E12 on Alpha Pro Tec 24

Your boiler is struggling to accurately measure the temperature of the water inside your hot water cylinder, which means it may fail to heat your water properly.

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

Cylinder NTC sensor fault

Engineer required

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

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