High Service
2.2 on Worcester Bosch ZB 7 27 HE

Your boiler is struggling to circulate water properly because it cannot communicate correctly with its internal water pump.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Service Function: Pump control mode

What causes this fault?

This code appears when the boiler has been manually put into a specific service setting by an engineer, which changes how the internal pump operates. It is caused by an installer navigating the diagnostic menu and leaving the pump control function active rather than returning it to the standard automatic setting. Because this is a configuration setting rather than a broken component, the boiler is simply waiting for a command to return to normal operation.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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