High
Fan runs at max. speed on Alpha CB 240 / 280

Your boiler's fan is running continuously at full speed, which indicates the system has detected a safety concern and is trying to clear the air inside the unit.

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

Follow section 'D' fault finding

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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