How much does it cost to fix Baxi error code Mains LED flashing?

Typical repair cost for the Baxi Mains LED flashing fault is £150-300 including labour.

Mains LED flashing High

Baxi Mains LED flashing Fault Code

Q: What does the Baxi Mains LED flashing fault code mean?

Your boiler is failing to communicate with its control panel, which means it cannot receive instructions to switch on for heating or hot water.

Also written as MAINSLEDFLASHING — same fault.

The Baxi Mains LED flashing fault code means: your boiler is failing to communicate with its control panel, which means it cannot receive instructions to switch on for heating or hot water.. It appears on 2 Baxi models in our database.

Technical description: Control knob is not on, or fault in wiring between control PCB and interface PCB / faulty control PCB.

Typical repair cost £150-300 (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 Mains LED flashing fault code

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

Source

Baxi Mains LED 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