High
31 on Saunier Duval Ecosy 24E

Your boiler has stopped working because a sensor that measures the temperature of the water currently leaving the unit is providing an invalid reading.

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

The heating flow thermistor is short circuited.

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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