High
9 E 25 on Saunier Duval Ecosy

Your boiler has sensed that the water inside is heating up far too quickly and has turned itself off to prevent overheating.

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

If the water temperature inside the boiler increases at greater than 4°C per second, the boiler will stop for 10 minutes. The display will show 9 alternated with E 25.

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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