Low
ECO-button lit on Worcester Bosch Greenstar 4000 Combi

Your boiler is currently set to 'Comfort Mode', which keeps the internal water hot so you get taps running warm faster.

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

Comfort mode

From this model's manual
Verified against the Worcester Boiler Rd 542i Combi 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 ECO button on the front control panel of your boiler.Press and hold the button until the light turns off if you wish to disable the feature to save energy.The light indicates the pre-heat function is active, not that there is a fault with your appliance.

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