BoilerFaultCodesThe 6 most common faults
Your boiler is not lighting, which means it cannot provide heat or hot water because the burner is failing to ignite.
Check that your gas stopcock is open and other gas appliances are working.Inspect the condensate pipe (the plastic pipe outside) for blockages or freezing.Press the 'Reset' button on the control panel to see if the boiler restarts.
Your boiler has switched itself off because the water pressure inside the system has dropped too low to operate safely.
Locate the filling loop (usually a silver flexible hose) under or near the boiler.Slowly open the valve(s) to allow fresh water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) tightly and restart the boiler.
Your boiler has failed to ignite and cannot produce heat or hot water because it isn't receiving gas or cannot create a flame.
Check that your gas emergency control valve (at the meter) is in the 'on' positionEnsure the gas isolation valve underneath the boiler is fully openPress and hold the RESET button for several seconds to clear the lockout
Your boiler has failed to ignite, which means it cannot heat your water or your home because it isn't getting a flame started.
Check that your gas emergency control valve and any boiler isolation valves are turned to the 'on' positionCheck if other gas appliances in your home, such as a hob, are working to confirm your gas supply is activePress the Reset button on the control panel to see if the boiler restarts
Your boiler has failed to ignite, which means your heating and hot water will not work until the gas supply is confirmed and the system is restarted.
Check that your gas emergency control valve (at the meter) is in the 'on' positionEnsure the gas isolation valve under the boiler is fully openPress and hold the RESET button for several seconds to restart the ignition sequence
Your boiler has tried to start but could not ignite the gas needed to generate heat.
Check that your gas emergency control valve at the meter is in the 'on' positionEnsure the gas isolation valve underneath the boiler is fully openPress and hold the 'RESET' button for a few seconds to try restarting the sequence
on the Ferroli Optimax
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