Low
CC 800 on Worcester Bosch 26 CDi Xtra

Your boiler has lost connection with its outdoor temperature sensor, which means it cannot adjust its settings based on the weather outside.

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

Check for any visible damage to the sensor or wiring on your home's outside wallSwitch the boiler off and back on again to see if the error clearsCheck if the batteries needs replacing if it is a wireless sensor model

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