High
F.63 on Vaillant ecoFIT Pure 412

Your boiler's computer has encountered an internal memory error, meaning it can no longer process instructions correctly and has safely shut down.

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

EEPROM 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

F.62View →F.64View →F.67View →

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