High
E15 on Saunier Duval Themaclassic Plus F30E

Your boiler is struggling to operate the internal valve that directs water between your heating and hot water, which may prevent the system from working correctly.

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

Stepper motor fault

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

F15View →

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