Medium
9 E 30 on Saunier Duval Ecosy

Your boiler has temporarily paused because it has detected a large temperature difference between the water leaving the boiler and the water returning to it, suggesting a blockage or poor circulation.

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

If the temperature difference between the central heating flow and return pipes exceeds 40°C, the boiler will stop for 2,5 minutes. The display will show 9 alternated with E 30.

DIY fix possible

Check that all radiator valves throughout your home are fully open.Ensure your central heating system pressure is set correctly in line with your user manual.Check for any blockages or trapped air by bleeding your radiators.

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