BoilerFaultCodesThe 6 most common faults
Your boiler has switched itself off because the internal water temperature has become too hot, usually caused by a lack of water flow through the system.
Check that your radiator valves are fully openEnsure your boiler pressure is between 1 and 1.5 bar on the gaugeReset the boiler by turning the control knob to 'RE' or pressing the reset button
Your boiler has failed to light several times and has shut down for safety, meaning you currently have no heating or hot water.
Check if your gas supply is active by testing another gas appliance like a hob.Check if your condensate pipe (the white plastic pipe outside) is frozen or blocked.Reset the boiler by turning the control knob to 'Reset' and holding for two seconds.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the internal filling loop, which is usually a small silver lever or a braided hose under the boiler.Open the filling valve slowly until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valve tightly and check that the fault code disappears.
Your boiler has lost its flame while trying to run, which means it cannot heat your water or your radiators.
Check that your gas supply is turned on at the meterIf you have a prepay meter, check that you have enough creditPress the Reset button on the boiler displayEnsure your external condensate pipe hasn't frozen in very cold weather
Your boiler has lost its flame while running, meaning it is not getting enough gas or the spark is failing to keep the burner lit.
Check if your gas meter has credit (if on a prepayment meter)Check if other gas appliances, like a hob, are working to confirm gas supplyReset the boiler by turning the mode knob to 'RE' and then back to the desired settingEnsure the external condensate pipe has not frozen if it is winter
Your boiler has automatically shut down for safety because it had to restart itself five times within a short period.
Switch off the power to the boiler at the fused spur or mains switch.Wait for 60 seconds to let the system reset completely.Switch the power back on and check if the boiler starts normally.
on the Ideal Independent System S15
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 Ideal 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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