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No light / Not a fault code on Worcester Bosch Greenstar i Junior

Your boiler has been manually set to run at full power for testing purposes and just needs to be switched back to its normal operating mode.

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 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 with a 'spanner' or 'service' icon on the control panel.Press and hold the service button briefly until the display or light returns to its normal status.The boiler should now respond to your thermostat and hot water taps as usual.

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