Low
CC 800 on Worcester Bosch Hideaway

Your boiler has lost communication with the outdoor temperature sensor, which means the system cannot automatically adjust its efficiency 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

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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