Medium
815 on Worcester Bosch Greenstar 8000 Style Combi

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

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

Low loss header temp. sensor faulty

Shared across the Greenstar 8000 Style range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 33 fault codes on the Greenstar 8000 Style Combi

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

200201202203204208224227228305306101710211037106510681073107410751076292029272946294829502963296429652966296729702971

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