Low
5 pulses on Worcester Bosch Greenstar 12 Ri

Your boiler has been left in its internal testing mode, which is usually only used by engineers during a service or setup.

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 max 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 horizontal dial on the front of the boiler control panel.Check if the dial is turned all the way to the right (maximum position).Turn the dial back to your desired temperature setting to exit service mode.

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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.

2 pulsesFast flashFlue pressure switchNo light

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