Low
Fast flash / Not a fault code on Worcester Bosch Greenstar 24i / 28i Junior

Your boiler is currently stuck in a manual testing mode used by engineers and needs to be switched back to its normal operating setting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Service mode selected to min, press service button to return to normal.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the button with a 'spanner' icon or labelled 'service'.Press the service button once to exit the testing mode.The blue light should stop flashing rapidly and return to a steady state.

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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 / OffLOCKOUTNo lightNo light / Not a fault codeOff (No light)Off / OffOn / OffSlow flashSteady on (Burner lit)

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