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

Typical repair cost for the Alpha Section D fault is £150-300 including labour.

Section D High

Alpha Section D Fault Code

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

Your boiler has identified a technical fault affecting how it senses temperature or processes internal airflow, which has caused it to shut down to prevent damage.

Also written as SECTIOND — same fault.

The Alpha Section D fault code means: your boiler has identified a technical fault affecting how it senses temperature or processes internal airflow, which has caused it to shut down to prevent damage.. It appears on 1 Alpha model in our database.

Technical description: Continuity across primary flow microswitch and PCB terminals 39, 40; DHW/Primary temp. sensor faulty; or Fan jammed/faulty winding

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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Alpha models that show the Section D fault code

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

240XE Repair: £150-300

Source

Alpha Section D 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