High
E04 on Keston C36p

Your boiler has stopped working because it cannot confirm that the internal fan, which clears exhaust gases, is spinning 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

Fan failure - boiler cannot detect fan rotation. Check fan operation and BOTH connectors onto fan.

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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