Low
CC 800 on Worcester Bosch 30i Junior

Your boiler has lost communication with the outside temperature sensor, which means it cannot automatically adjust its performance based on the weather.

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

Outdoor sensor defect available when accessory outdoor sensor is connected

DIY fix possible

Locate the external weather sensor on your outside wallCheck for any obvious damage to the sensor or its wiringPress the Reset button on the boiler control panel

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