High
F.11 on Vaillant Turbomax Plus VUW 242EH

Your boiler has detected a faulty electrical signal from the temperature sensor that monitors the water returning to the unit, meaning it cannot accurately judge when to heat your home.

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

Short circuit - return-NTC (<130°C) | NTC-plug shorted to casing, NTC defective

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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