High
E15 on Heatline Solaris

Your boiler has detected an unusual temperature difference between the water leaving the unit and the water returning to it, often caused by a circulation blockage or a sensor failure.

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

Sensor difference fault (Flow/Return)

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

E03View →E05View →E06View →

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