How much does it cost to fix Baxi error code C neon flashing?

Typical repair cost for the Baxi C neon flashing fault is £120-280 including labour.

C neon flashing High

Baxi C neon flashing Fault Code

Q: What does the Baxi C neon flashing fault code mean?

Your boiler has detected that water isn't moving through the internal pipes effectively, which prevents it from heating up safely.

Also written as CNEONFLASHING — same fault.

The Baxi C neon flashing fault code means: your boiler has detected that water isn't moving through the internal pipes effectively, which prevents it from heating up safely.. It appears on 1 Baxi model in our database.

Technical description: Primary water flow switch not operated; go to section C

Typical repair cost £120-280 (including labour)

DIY fix possible

Check that the boiler pressure is between 1.0 and 1.5 bar on the gaugeOpen any radiator valves that are turned off to ensure water can flowEnsure the main stop tap and any isolation valves under the boiler are fully open

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Baxi models that show the C neon flashing fault code

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

Combi 130e Repair: £120-280

Source

Baxi C 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 27 April 2026