Medium
815 on Worcester Bosch Greenstar 8000 Style

Your boiler is struggling to accurately monitor the temperature of the water circulating through your heating system, which means it may not heat your radiators or hot water as efficiently as it should.

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

Low loss header temp. sensor faulty

Engineer required

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

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