Medium
9 E 30 on Saunier Duval Ecosy 24E

Your boiler has temporarily stopped because it is struggling to circulate water properly through your radiators, causing a large heat difference between the pipes.

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 openBleed your radiators to remove any trapped air that may be blocking water flowEnsure your system pressure is at the correct level, usually between 1.0 and 1.5 bar

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