BoilerFaultCodesThe 6 most common faults
Your boiler has detected that the water is not flowing through your heating system correctly, so it has shut down to prevent overheating.
Check that all radiator valves are fully open.Check your boiler's pressure gauge and ensure it is between 1 and 1.5 bar, topping up via the filling loop if necessary.Check if your heating system pump is running or feels warm to the touch.
Your boiler has detected that water is not flowing properly around your heating system, so it has safely shut itself down to prevent overheating.
Check that all your radiator valves are fully open.Inspect your pressure gauge to ensure it is between 1 and 1.5 bar.If the pressure is below 1 bar, use the filling loop to top it up to the correct level.Restart the boiler to see if the error clears.
Your boiler has detected that the water pressure inside the system is too low, which prevents it from operating safely.
Locate the external filling loop, which is a silver braided hose with one or two manual taps underneath the boiler.Open the tap(s) slowly to allow water into the system until the pressure gauge on the front panel reads between 1.0 and 1.5 bar.Close the tap(s) firmly and ensure no water is leaking from the connection.
Your boiler's internal water pressure has climbed too high and the system is safely shutting down to prevent potential leaks or damage.
Check that the filling loop valves under the boiler are fully closedBleed water from a radiator using a bleed key to reduce system pressureMonitor the pressure gauge until it returns to between 1 and 1.5 barReset the boiler once the pressure is within the normal range
Your boiler is struggling to move water around your heating system effectively, so it has shut down to prevent overheating.
Check your radiator valves to ensure they are fully openCheck the central heating system pressure gauge and top up to 1.5 bar if low (using the filling loop)Turn the boiler off and on again at the power switch to clear the temporary error
Your boiler is struggling to move water through your radiators or pipes quickly enough, which is preventing it from heating your home properly.
Check all radiator valves in your home are fully openCheck your boiler pressure gauge to ensure it is between 1.0 and 1.5 barBleed any trapped air from your radiators using a radiator key
on the Ariston Egis
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