High
Section D on Alpha 240XE

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

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

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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