BoilerFaultCodesThe 6 most common faults
Your boiler has detected that the water pressure inside your heating system is either too low or too high, so it has safely shut down to prevent damage.
Locate the external filling loop, which is usually a small silver braided hose with one or two valves underneath the boiler.Gradually open the valve(s) to let water in until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valve(s) tightly to stop the flow of water and check if the error code clears.
Your boiler has switched itself off because it has become too hot internally, likely due to a lack of water flow or a blockage.
Check that your central heating pressure is between 1.0 and 1.5 bar on the pressure gauge.Ensure all radiator valves and internal stop taps are fully open to allow water to flow.Try resetting the boiler by pressing the 'Reset' button on the control panel.
Your boiler has temporarily stopped working because the water pressure inside the system has risen above the safe limit.
Turn off the heating and let the system cool down completely.Locate a radiator and place a cloth and container beneath the bleed valve.Open the bleed valve slightly to let water out until the pressure gauge drops to around 1.0 to 1.5 bar, then close the valve tightly.
Your boiler is struggling to detect the flow of water through its system, which means it cannot safely heat your home or provide hot water.
Full guide for 20Your boiler is struggling to accurately read the temperature of the water returning to it, which prevents it from heating your home reliably.
Full guide for 40Your boiler is having trouble detecting the temperature of the water coming from your taps, which means it cannot heat your hot water properly.
Full guide for 50on the Atag iC28
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 Atag 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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