High
LED flashing after fan on Sime Ecomfort HE Combi

Your boiler is unable to start up safely because the internal fan, which clears waste gases, is not spinning correctly or communicating with the control board.

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.

What the manual says

Manufacturer manual

Fan fault — check fan wiring and operation

From this model's manual
Verified against the P3 Sime Murelle He System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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