BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the filling loop (a silver flexi-hose with one or two valves) underneath the boiler.Open the valves slowly to allow mains cold water into the system until the pressure gauge reads between 1 and 1.5 bar.Close the valves tightly and check the boiler display to see if the error has cleared.
Your boiler failed to light on its first try and needs a quick reset to attempt to restart the burner.
Locate the reset button on your boiler control panel.Press and hold the reset button for 2-3 seconds.Wait up to 60 seconds to see if the boiler ignition cycles successfully.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to function safely.
Locate the filling loop (a silver flexi-hose) or internal filling key under the boiler.Gradually open the valve(s) to let mains water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) tightly and turn the boiler off and on again to clear the error.
Your boiler is trying to start up but is failing to light the flame, so it has shut itself off to prevent a build-up of unburnt gas.
Full guide for A01Your boiler is struggling to keep its internal flame lit steadily and has stopped working to keep you safe.
Full guide for A07Your boiler has detected that water is not moving through the system correctly, which is preventing it from heating your home or water safely.
Full guide for A17on the Ariston Genus 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
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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