Medium
1068 on Worcester Bosch Greenstar 4000

Your boiler is struggling because it has lost the signal from an external sensor that helps it calculate the right amount of fuel to burn.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

Outside temp. sensor or lambda probe faulty.

Engineer required

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

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