High
A1 281 on Worcester Bosch Greenstar i

Your boiler's water pump is struggling to circulate water, which means the system cannot effectively move heat to your radiators or taps.

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

Pump stuck or running dry

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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