High
F19 on Saunier Duval Enviroplus

Your boiler has detected that a temperature sensor has come loose from the pipe it monitors, meaning the system can no longer accurately read the water temperature.

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 flow NTC unclipped

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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