High
F.xx on Vaillant ecoFIT Pure 418

Your boiler has encountered a general communication or system error that it cannot identify with a specific sub-code, causing it to stop running for safety.

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 messages (refer to the table in the appendix)

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.00View →F.22View →F.75View →

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