Low
5 pulses / No light on Worcester Bosch Greenstar i Junior

Your boiler has been accidentally switched into a specific testing mode used by engineers, rather than having a mechanical breakdown.

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.

Technical description

Not a fault code. Service mode selected to max, press service button to return to normal.

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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