High
LED 1: On, LED 2: On on Halstead Buckingham 4

Your boiler is failing to clear air from the system before starting, which is preventing it from firing up safely.

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

Simultaneous: Lighting Sequence-Fan/APS (Check connection & operation)

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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