High
Fan runs at max. speed on Alpha CD28

Your boiler's fan is running continuously at top speed, which indicates the internal computer has detected a safety concern and is trying to vent the system.

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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