High
1019 on Worcester Bosch Greenstar 4000

Your boiler has detected that the water pump is either not communicating properly or is the wrong type for your specific model, which prevents the system from circulating heat effectively.

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

Incorrect pump type detected | Pump communication failure or wrong pump is fitted (i.e. non-ErP).

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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Related fault codes

1018View →

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