Medium
F.13 on Vaillant ecoFIT Pure 412

Your boiler has lost the signal from the sensor that monitors your hot water tank’s temperature, so it may stop heating your water to prevent overheating.

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

Domestic hot water cylinder temperature sensor short circuit

Engineer required

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

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