High
19 on Saunier Duval Thema F 30 E Plus

Your boiler has lost the signal from the sensor that monitors the temperature of the water flowing to your radiators, causing it to stop working for safety reasons.

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 not connected to pipe

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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