Low
2 pulses on Worcester Bosch Greenstar 30i

Your boiler is accidentally stuck in a technician's testing mode 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

Check service mode switch is in minimum position

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 small selector switch on the control panelEnsure the switch is turned away from the 'minimum' or 'service' iconsPress the Reset button to clear the flashing light

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