High
F.10 on Vaillant ecoFIT Pure 425

Your boiler has stopped working because a sensor that monitors water temperature has developed a faulty faulty connection or failed completely, causing the system to shut down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flow temperature sensor short circuit

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.11View →F.12View →

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