BoilerFaultCodesWhat the manual says
Manufacturer manualService 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 button with a 'spanner' or 'service' icon on the control panel.Press and hold the service button briefly until the display or light returns to its normal status.The boiler should now respond to your thermostat and hot water taps as usual.
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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 light5 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 lightOff (No light)Off / OffOn / OffSlow flashSteady on (Burner lit)