Low
4-b3 on Worcester Bosch Greenstar 2000

Your boiler is notifying you that the settings for its automatic outdoor temperature sensors are incorrectly configured or out of their allowed range.

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.

Technical description

End point of the heating curve for weather-compensated control: 20... 90 °C.

DIY fix possible

Navigate to the service menu on the control panelLocate the weather compensation settingsAdjust the heating curve end point to a value between 20°C and 90°CPress the reset button to clear the notification

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Related fault codes

4-b1View →4-b2View →

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