High
LED 1 Fast Flashing (8Hz) on Halstead Buckingham 4

Your boiler's computer is experiencing a temporary processing confusion that has caused it to stop working to protect the system.

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

Software Error

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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