Medium
E12 on Saunier Duval Thema F 30 E Plus

Your boiler's temperature sensor for hot water has stopped working correctly, meaning your taps may not get warm or the temperature will be inconsistent.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

DHW thermistor (NTC) fault

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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