High
F63 on Heatline Capriz Plus

Your boiler's internal computer has encountered a critical memory error and can no longer safely control the heating system, requiring professional attention.

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

Fault in the main board memory

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

F62View →F64View →

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