Medium
5 pulses on Worcester Bosch Greenstar 30i

Your boiler is currently stuck in a manual testing mode normally used by engineers during a service.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Check service mode switch is in max 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 service mode switch (often a small dial or toggle) on the control panel.Check if the switch has been accidentally moved to the 'Max' or 'Min' setting.Turn the switch back to its normal operating position (usually the middle or 'Off' position).

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