High
neon flashing (Section D) on Baxi Combi 80e

Your boiler is failing to clear its system of air before starting, so it has safely shut down to prevent ignition.

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

Air pressure switch not proved

From this model's manual
Verified against the Baxi Boiler Combi 80 Maxflue 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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A cover plan would handle faults like neon flashing (Section D): no call-out fees, no surprise bills.

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All 12 fault codes on the Combi 80e

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

Burner on neon NOT illuminatedFlame Failure (Red Light) ONneon flashing (Burner lights)neon flashing (Fan runs)neon flashing (Section E)neon flashing (Section H & K)neon flashing (Section I)neon flashing (Section J)neon flashing (Spark/Ignition)Red 'Flame Failure' neon litReset neon illuminated (Red)

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