High
E17 on Johnson Starley C10d

Your boiler has detected that a safety sensor hasn't moved into the correct position to allow the fan and burner to start safely.

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

Air flow switch stuck open

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

E01View →E16View →

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