BoilerFaultCodesThe 6 most common faults
Your boiler has sensed that the water inside IT is getting too hot too quickly, causing it to shut down for safety.
Check that all radiator valves are fully open to allow water to circulate.Ensure there is no air trapped in the system by bleeding your radiators.Check that your boiler pressure is between 1 and 1.5 bar on the front gauge.
Your boiler has tried to start up, but it cannot detect a flame to keep it burning.
Check that your gas supply is working by testing another gas appliance like a hob.Locate the reset button on your boiler control panel and press it for about 5 seconds.Check that your pre-payment gas meter has credit if applicable.
Your boiler's internal computer has encountered a software glitch or a communication error that is preventing it from starting safely.
Locate the reset button on the front control panelPress and hold the reset button for five secondsWait for the boiler to restart; if the code returns, a gas engineer is required
Your boiler has detected an issue with the incoming electricity supply or its internal power connection.
Check that the boiler's fused spur switch and main circuit breaker have not tripped.Unplug the boiler or switch off the fused spur for 30 seconds, then turn it back on to reset the system.
Your boiler has detected that water is not circulating properly because the internal pump is either jammed or has air trapped inside it.
Check your boiler pressure gauge to ensure it is sitting between 1 and 1.5 bar.If the pressure is low, use the filling loop to top it back up.Reset the boiler using the reset button to see if the pump clears and restarts.
Your boiler has failed to light the flame, which means it has stopped working to keep you safe.
Full guide for EAon the Worcester Bosch Greenstar 28CDi Compact ErP
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 Worcester Bosch 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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