Low
i15 on Worcester Bosch Greenstar Heatslave II

Your boiler is simply displaying the current outdoor temperature because a weather sensor is connected, which is a normal status reading rather than a fault.

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

Out door temperature - This is the out door temperature displayed in real time (rounded to 0.5°C units). Only available if a Weather Compensation sensor has been fitted and Weather Compensation 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.

DIY fix possible

No action is required as this is a status notification, not an error.Check your boiler display manual if you wish to toggle the default display view back to the target room temperature.

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