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 has stopped working because the amount of water inside your heating system has dropped below the minimum level required to run safely.
Locate the filling loop (usually a silver braided hose with a valve) underneath the boiler.Open the valve slowly to allow mains cold water to enter the system until the pressure gauge on the front reads between 1.0 and 1.5 bar.Close the valve tightly to stop the flow and ensure the boiler resets itself.
Your boiler has stopped working because it has failed to light the burners, meaning it cannot produce heat or hot water.
Full guide for E01Your boiler's heating water temperature sensor has detected a fault, meaning the system can no longer accurately read how hot the water is.
Full guide for E05Your boiler has detected a problem with the temperature sensor on the hot water supply, which means it cannot accurately measure how hot the water is.
Full guide for E06on 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