Medium
12 on Alpha Intec 40GS2

Your boiler is struggling to detect the temperature of your hot water cylinder, which means it may fail to heat your taps or shower correctly.

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 sensor fault (InTec S and FlowSmart only) - Incorrect cylinder sensor resistance

Engineer required

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

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