BoilerFaultCodesThe 6 most common faults
Your boiler has detected that water is not flowing through the system correctly, which is preventing it from heating your home properly.
Check that all radiator valves throughout your home are fully open.Inspect the boiler pressure gauge and top it up to 1.5 bar using the filling loop if it is below 1.Reset the boiler using the reset button on the control panel.
Your boiler is struggling to push water around your heating system because the flow is blocked or restricted.
Check that all radiator valves throughout your house are fully openEnsure your system pressure is at the recommended level of 1.5 barBleed your radiators to remove any trapped air that might be blocking water flow
Your boiler is struggling to move water around your heating system effectively, usually because there is trapped air, a blockage, or low water pressure.
Check your boiler pressure gauge and top it up to 1.5 bar using the filling loop if it is below 1 barBleed all radiators in the house to release trapped airEnsure all radiator valves are fully open
Your boiler has detected that the water pressure in your heating system is too low to operate safely, so it has shut down to protect itself.
Locate the filling loop, which is usually a flexible metal hose with one or two small valves connecting your cold mains pipe to your heating pipework.Open the valve(s) slowly to allow water into the system while watching the pressure gauge on the front of the boiler.Stop filling as soon as the needle reaches the green zone, typically between 1.0 and 1.5 bar, then tightly close the valve(s).
Your boiler has detected that the water pressure inside the system is dangerously high, which can cause internal leaks or safety valve discharge.
Check that the filling loop valves are fully closedBleed water from a radiator using a bleed key to reduce the pressureMonitor the pressure gauge to ensure it returns to between 1 and 1.5 barReset the boiler once the pressure is stabilised
Your boiler has detected that hot water is not flowing around your heating system properly, so it has shut down to prevent overheating.
Check your boiler pressure gauge and ensure it is between 1 and 1.5 barIf the pressure is low, use the filling loop to top it up to the correct levelEnsure all radiator valves are fully open to allow water to circulate freely
on the Ariston E-Combi One 30
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 Ariston 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