LED flashing after fan High

Sime LED flashing after fan Fault Code

Also written as LEDFLASHINGAFTERFAN — same fault.

The Sime LED flashing after fan fault code means: 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.. It appears on 12 Sime models in our database.

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 fault — check fan wiring and operation
Typical repair cost £180-£350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like LED flashing after fan: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Sime models that show the LED flashing after fan fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Sime LED flashing after fan fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026