Low
ECO on Worcester Bosch Greenstar Heatslave II

Your boiler is simply in energy-saving mode, which means it will not pre-heat your hot water in order to save on fuel costs.

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

Eco mode is active

From this model's manual
Verified against the Worcester Bosch Greenstar Heatslave Ii 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.

What causes this fault?

This is not a mechanical failure but a user-selected settings choice. It occurs when the 'Eco' button has been pressed, instructing the boiler to disable the internal pre-heat function which normally keeps a small reservoir of water hot at all times. While this saves money on heating bills, it means you may have to wait a little longer for hot water to reach your taps.

DIY fix possible

Locate the ECO button on the boiler control panelPress and hold the ECO button until the light turns off if you prefer instant hot waterLeave the setting as it is if you wish to continue saving energy

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