BoilerFaultCodesWhat the manual says
Manufacturer manualNot a fault code. Service mode selected to max, press service button to return to normal.
From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar I Junior installation & service manual.
DIY fix possible
Locate the blue 'Service' button on the front control panel.Press and hold the 'Service' button for several seconds.Wait for the indicator light to stop flashing and return to its standard display mode.
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All 38 fault codes on the Greenstar 24i / 28i Junior
Seeing a different code? Every code this model can display, in one place.
2 pulses2 pulses / No light2 pulses No light5 pulses5 pulses No light6a1213141516171819109115A8Blue indicator light flashingBlue indicator light offBlue light onDouble flash Blue lightEAERRORFAFast flashFast flash (Reset button Off)Fast flash / FlashingFast flash / Not a fault codeFast flash / OffLOCKOUTNo lightNo light / Not a fault codeOff (No light)Off / OffOn / OffSlow flashSteady on (Burner lit)