Medium
1068 W on Worcester Bosch 30i Junior

Your boiler is struggling to know how cold it is outside, which can prevent it from heating your home efficiently or at all.

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 temperature sensor defective – check the connecting lead

Engineer required

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

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