High
neon flashing (Fan runs) on Baxi Combi 80 Maxflue

Your boiler has detected that the fan is spinning but not reaching the required speed to safely clear waste gases, preventing the burner from lighting.

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 fails to run at maximum speed; refer to Section D.

From this model's manual
Verified against the Combi Instant 80e Current 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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Related fault codes

Flame failure neonView →

All 47 fault codes on the Combi 80 Maxflue

Seeing a different code? Every code this model can display, in one place.

© neon flashing10111213141522232425262728293031Burner On NeonBurner on neon NOT illuminatedDHW FLOW SWITCHFANFlame Failure (Red Light) ONFlame Failure Neonneon flashingneon flashing (Burner lights)neon flashing (Pump runs)neon flashing (Section D)neon flashing (Section E)neon flashing (Section H & K)neon flashing (Section I)neon flashing (Section J)neon flashing (Spark/Ignition)neon illuminatedPower On NeonPressure of 3 or greaterRed 'Flame Failure' neon litReset neon illuminated (Red)Safety thermostat activated且 neon flashing布 & 皿 neons flashing布 neon flashing毛 neon flashing皿 neon illuminated血 neon illuminated閃 neon flashing閃 neon illuminated

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