Low
5 pulses on Worcester Bosch Greenstar i Junior

Your boiler is currently in a manual testing mode set by the technician, which makes it run at its highest speed.

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

Not a fault code. Service mode selected to max, press service button to return to normal.

From this model's manual
Verified against the Worcester Bosch Greenstar I Junior 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 button labeled 'Service' on the front control panel of your boiler.Press the 'Service' button once to exit the testing mode.Check that the flashing light stops and the boiler returns to its standard operating display.

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