Low
CC 800 on Worcester Bosch Greenstar Ri

Your boiler is struggling to read the outdoor temperature, so it is defaulting to a standard internal setting to keep your heating running.

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

Outdoor sensor defect

From this model's manual
Verified against the Worcester Bosch Greenstar Ri installation & service manual, page 66.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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Related fault codes

CC 801View →CC 802View →

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