High
9 25 blinking on Saunier Duval Ecosy

Your boiler has stopped working because it cannot move the hot water around your house, so it has locked itself for safety.

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 fault (E 25) persists after 5 attempted relights, the boiler shuts down and requires a manual reset. Check that the pump is operating, the central heating isolating cocks are open and that there is circulation in the system.

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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