BoilerFaultCodesBaxi neon (flashing) Fault Code
Also written as NEONFLASHING — same fault.
The Baxi neon (flashing) fault code means: your boiler is simply warming up its internal water supply to ensure hot water is ready the moment you turn on a tap; this is a normal operational light and not a fault.. It appears on 25 Baxi models in our database.
Technical description: DHW preheating circuit active (internal function indication)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Search the official register for a qualified engineer in your area.
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A cover plan would handle faults like neon (flashing): no call-out fees, no surprise bills.
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Baxi models that show the neon (flashing) fault code
Click a model for the full fault code list and model-specific repair notes.
- 105e Repair: £120-250
- Combi 105 HE Repair: £200-450
- Combi 80 Maxflue
- Combi 80 Maxflue Repair: £180-£350
- Combi 80 Maxflue Repair: £90-160
- Combi 80 Maxflue Repair: £120-£350
- Combi 80 Maxflue Repair: £120-300
- Combi 80 Maxflue Repair: £250-450
- Combi 80e
- Combi 80e Repair: £180-£350
- Combi 80e Repair: £90-160
- Combi 80e Repair: £120-£350
- Combi 80e Repair: £120-300
- Combi 80e Repair: £250-450
- Combi Elite
- Combi Elite Repair: £180-350
- Combi Elite Repair: £90-160
- Combi Elite Repair: £120-300
- Combi Elite Repair: £90-280
- Combi Instant 80/105 HE
- Combi Instant 80/105 HE
- Combi Instant 80/105 HE Repair: £150-300
- Combi Instant 80/105 HE Repair: £120-220
- Combi Instant 80/105 HE Repair: £150-300
- Combi Instant 80/105 HE Repair: £120-250
Source
Baxi neon (flashing) fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026