BoilerFaultCodesHalstead P Fault Code
The Halstead P fault code means: your boiler is struggling to operate because the electrical supply is unstable or too low, preventing the flame from starting safely.. It appears on 1 Halstead model in our database.
Technical description: Power supply error/ No flame - Low mains voltage
DIY fix possible
Check if other electrical appliances in your home are flickering or underperformingEnsure the boiler is plugged directly into its fused spur and not an extension leadReset the boiler by turning the control knob to the 'Reset' position for five seconds and then back to 'On'
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Halstead models that show the P fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Halstead P 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