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 completely lost power and the screen is blank, meaning it is not currently working.
Check that the fused spur switch supplying power to the boiler is turned on.Inspect your home's fuse box or consumer unit to see if the circuit breaker for the boiler has tripped.If the breaker has tripped, try resetting it once; if it trips again immediately, stop and call an engineer.
Your boiler has detected a missing or disconnected internal memory chip on its main circuit board, which prevents it from operating correctly.
Full guide for C2Your boiler has temporarily shut down because the water inside it has become too hot.
Full guide for L and 1on the Ideal Classic
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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