High
Pump does not run on Worcester Bosch Greenstar 15i System

Your boiler is failing to circulate water through your radiators or hot water tank, meaning your home will not be able to heat up.

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

External system controls not creating demand, faulty control board, or faulty pump

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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