Emergency
1 8 on Saunier Duval Ecosy

Your boiler has shut down because it has detected that the water inside it has become dangerously overheated.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

The heating flow thermistor is detecting a temperature in excess of 100°C.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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