High
F.63 on Vaillant ecoFIT pure

Your boiler's computer memory has encountered an internal error, which prevents it from operating correctly and requires a specialist to reset or replace the main circuit board.

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 error

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.65View →

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