High
Safety system failure on Halstead Finest Gold

Your boiler's computer is unable to perform its own safety checks and has stopped working to prevent any potential risks.

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

Failure of internal self checking system • Check PCB

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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