High
F9 on Heatline Capriz 24

Your boiler's computer is having trouble talking to its internal parts, which has caused it to stop working completely to stay safe.

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

Communication error / Printed Circuit Board (PCB) fault

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

F1View →F2View →

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