High
F19 on Vaillant ecoMAX Pro 18E

Your boiler has lost the connection to the temperature sensor that monitors your heating system, meaning it cannot tell how hot the water is and has shut down 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

Central heating NTC unplugged

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

F20View →

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