High
E19 on Saunier Duval Thema F 30 E Plus

Your boiler has lost connection with a temperature sensor that monitors the heating system, meaning it cannot safely determine how hot the water is getting.

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 thermistor (NTC) disconnected

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

E05View →

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