BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Locate the external filling loop, which is usually a small metal or braided hose located under the boiler.Open the small valve(s) on the loop to allow mains water to enter the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valve(s) tightly and check that the error code has cleared.
Your boiler has detected that the water pressure inside your heating system is either too high or too low for it to operate safely.
Check the pressure gauge on the front of the boiler; if it is below 1 bar, your system needs to be re-pressurised.Locate the external filling loop (typically a silver flexible hose with one or two valves) connected to the underside of the boiler.Open the valve(s) slowly to let water in until the gauge needle sits between 1 and 1.5 bar, then ensure the valves are tightly closed.
Your boiler is failing to light the internal flame, which means it cannot produce any heat or hot water.
Full guide for F1Your boiler has detected that it is dangerously hot and has shut itself down to prevent any damage to the unit.
Full guide for F3Your boiler has detected an issue with the internal ventilation system that pushes waste gases outside, so it has safely shut itself down to prevent operation.
Full guide for F5Your boiler has detected an issue with the flame detection system, meaning it cannot reliably tell if the burner is lit, so it has safely shut itself down to prevent gas from escaping.
Full guide for F8on the Ferroli Maxima 35 S
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Ferroli shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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