Medium
F.13 on Vaillant ecoTEC Pro 30

Your boiler has lost the ability to accurately measure the temperature of the water used for your taps, which means it has stopped heating your hot water to prevent potential 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 sensor short circuit

Engineer required

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

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Related fault codes

F.10View →F.11View →

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