High
F0 280 on Worcester Bosch Junior 24i

Your boiler's internal computer has developed a fault or is not communicating correctly, meaning the system cannot safely operate.

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

Control box or the heat control module (HCM) is defective – control box and connections need checking or HCM might not be inserted properly and need replacing

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

F7View →E9View →

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