High
S.35 on Heatline Compact 24

Your boiler is having trouble managing the airflow needed to operate safely and has shut down to prevent any issues.

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

The speed of fan in functioning phase is outside tolerance

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

S.34View →

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