High
F.11 on Vaillant ecoFIT Pure 412

Your boiler has detected a faulty connection to a sensor that measures the temperature of the water returning to the system, causing it to stop运行 as a safety precaution.

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

Return 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.10View →

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