How much does it cost to fix Alpha error code Section G?

Typical repair cost for the Alpha Section G fault is £150-350 including labour.

Section G High

Alpha Section G Fault Code

Q: What does the Alpha Section G fault code mean?

Your boiler is struggling to control how much heat it produces, which likely means it cannot sustain a steady temperature for your radiators or hot water.

Also written as SECTIONG — same fault.

The Alpha Section G fault code means: your boiler is struggling to control how much heat it produces, which likely means it cannot sustain a steady temperature for your radiators or hot water.. It appears on 1 Alpha model in our database.

Technical description: Burner output does not modulate (Main PCB plug connections, modulating coil faulty, or Main PCB terminals 41, 42)

Typical repair cost £150-350 (including labour)

Engineer required

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

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Alpha models that show the Section G fault code

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

240XE Repair: £150-350

Source

Alpha Section G fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026