Halstead A Fault Code
The Halstead A fault code means: your boiler has stopped working because its internal computer or the burner has encountered a serious communication error.. It appears on 1 Halstead model in our database.
Technical description: PCB error/No flame - Internal error
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Halstead models that show the A fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Halstead A fault code information on this page is sourced and cross-checked against the official Halstead service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026