High
E8 on Remeha Quinta 30

Your boiler has detected that the water leaving it is significantly hotter than the water returning, meaning heat isn't circulating properly through your radiators.

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

Difference between flow and return temperature too large

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

E9View →E10View →

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