Ferroli LED5 bar (Flashing) Fault Code
Also written as LED5BARFLASHING — same fault.
The Ferroli LED5 bar (Flashing) fault code means: your boiler has stopped heating because the water pressure inside the system has dropped too low to operate safely.. It appears on 1 Ferroli model in our database.
Technical description: Insufficient pressure in central heating system
DIY fix possible
Locate the external filling loop, which is a silver braided hose connected between two valves underneath the boiler.Open the valves slowly to allow mains cold water into the system while watching the pressure gauge.Close the valves tightly once the needle reaches the green zone, typically between 1.0 and 1.5 bar.
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Gas Safe Register →Ferroli models that show the LED5 bar (Flashing) fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ferroli LED5 bar (Flashing) fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026