Medium
1068 on Worcester Bosch Greenstar 27CDi

Your boiler is struggling to accurately read either the outside air temperature or the gas combustion quality, which may prevent it from heating your home efficiently.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Outside temp. sensor or lambda probe faulty

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 84.
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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