Low
5 pulses / No light on Worcester Bosch Greenstar 12i System

Your boiler is currently in a manual testing mode used by engineers, rather than a standard fault state, so it is running at maximum temperature temporarily.

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 boiler control panel.Press the button once to exit the testing mode.Wait a moment for the light to stop flashing and for the boiler to return to its normal operating cycle.

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