High
E9 on Remeha Gas 610 Eco Pro

Your boiler has detected that water isn't moving through the system correctly or is overheating too quickly, causing it to shut down to prevent damage.

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

Water flow problem: Flow and return temperature sensors swapped or insufficient flow (delta T too high)

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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Related fault codes

E7View →

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