High
No code on Worcester Bosch Highflow 300

Your boiler is struggling to drain away the water it creates while running, which causes it to shut down to prevent internal flooding.

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

Condensate trap / 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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