How much does it cost to fix Baxi error code neon flashing (Section D)?

Typical repair cost for the Baxi neon flashing (Section D) fault is £150-250 including labour.

neon flashing (Section D) High

Baxi neon flashing (Section D) Fault Code

Q: What does the Baxi neon flashing (Section D) fault code mean?

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

Also written as NEONFLASHINGSECTIOND — same fault.

The Baxi neon flashing (Section D) fault code means: your boiler is failing to clear its system of air before starting, so it has safely shut down to prevent ignition.. It appears on 2 Baxi models in our database.

Technical description: Air pressure switch not proved

Typical repair cost £150-250 (including labour)

Engineer required

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

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Baxi models that show the neon flashing (Section D) fault code

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

Source

Baxi neon flashing (Section D) 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 27 April 2026