Medium
d5 on Worcester Bosch Greenstar 25 HE Combi

Your boiler is struggling to accurately read the temperature of the water being sent out to your radiators because a sensor responsible for monitoring this flow has developed a fault.

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

External primary NTC on low loss header defect.

Engineer required

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

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Related fault codes

d1View →d3View →

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