Power ON (Green LED) blinking High

Halstead Power ON (Green LED) blinking Fault Code

Also written as POWERONGREENLEDBLINKING — same fault.

The Halstead Power ON (Green LED) blinking fault code means: your boiler has stopped working because it doesn't have enough water inside the system to operate safely.. It appears on 2 Halstead models in our database.

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: Low water pressure or flow switch fault.
Typical repair cost £80-150 (including labour)

DIY fix possible

Locate your boiler's filling loop, which is usually a silver braided hose connecting two pipes under the boiler.Open the valves on the filling loop to allow cold mains water into the system until the pressure gauge reads between 1 and 1.5 bar.Close the valves tightly and check the front panel to see if the blinking light has stopped.

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Halstead models that show the Power ON (Green LED) blinking fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Halstead Power ON (Green LED) blinking 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 27 April 2026