Medium
12 on Alpha E-Tec R

Your boiler is struggling to detect the temperature of your hot water cylinder, meaning it cannot reliably heat your water.

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 - Incorrect cylinder sensor resistance value

Engineer required

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

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