High
F7 328 on Worcester Bosch Greenstar CDi Compact

Your boiler's main electronic brain has encountered a permanent internal fault and is no longer able to operate your heating or hot water safely.

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

Internal error. Replace control board

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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