Low
CC on Worcester Bosch Greenstar 36 CDi Compact

Your boiler has lost connection to the weather sensor outside, but it should still continue to keep your home warm using its backup settings.

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/Worcester Bosch Greenstar Cdi Compact 6720803800 installation & service manual.
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

C1View →C7View →

All 34 fault codes on the Greenstar 36 CDi Compact

Seeing a different code? Every code this model can display, in one place.

8C9UA1A3A7A8b7C1C4C6C7CECFD1D3D4E2E3E4E5E9EAECEDEEEFF0F7FAFbFDH5TTB

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