Medium
On / Off (HW fault) on Worcester Bosch Greenstar i Junior

Your boiler is heating the radiators normally, but it is failing to switch over to provide hot water to your taps.

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.

Technical description

Boiler not operating during hot water demand (CH ok). Check: Flow Sensor Test, Diverter valve, Control board.

Engineer required

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

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