BoilerFaultCodesThe 6 most common faults
01
E01-612 High Engineer
Your boiler has failed to ignite because it cannot detect a flame, meaning it has safely shut itself down to prevent gas from building up.
Full guide for E01-61202
E01-930 High Engineer
Your boiler has lost the ability to properly detect the flame, so it has safely shut down to prevent gas from flowing without a fire.
Full guide for E01-93003
E01-598 High Engineer
Your boiler is failing to light the flame because the internal electrical connection responsible for triggering ignition is likely faulty or disconnected.
Full guide for E01-59804
E01-599 High Engineer
Your boiler has detected an internal issue with how heat is transferred between the burner and your water, meaning it has shut itself down to prevent damage.
Full guide for E01-59905
E01-602 High Engineer
Your boiler's water circulation pump or its electrical connection has failed, meaning your heating and hot water cannot function because the system can no longer push hot water around your radiators and taps.
Full guide for E01-60206
E58-079 High Engineer
Your boiler's main electronic brain is experiencing an internal communication or hardware error, which causes the appliance to safely lock out.
Full guide for E58-079on the Worcester Bosch 28i RSF
Flame rectification probeIgnition electrodePCBFlame sensor electrodeWiring harnessIgnition lead
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
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