Medium
H11 on Worcester Bosch Greenstar i

Your boiler is struggling to accurately measure the temperature of your hot water, which means it may be unable to heat it correctly for your taps.

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

DHW temperature sensor defect.

Engineer required

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

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