Low
2 pulses on Worcester Bosch Greenstar 12 Ri

Your boiler has been left in a manual testing mode after a service or inspection 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 switch in min position.

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch 12ri installation & service 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 (or dial) on the boiler control panel.Ensure the switch is moved from the 'Min' or 'Service' position back to the 'Normal' or 'Off' position.Perform a simple reset by pressing the reset button to clear the flashing light.

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All 5 fault codes on the Greenstar 12 Ri

Seeing a different code? Every code this model can display, in one place.

5 pulsesFast flashFlue pressure switchNo light

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