High
F.61 on Vaillant ecoFIT pure

Your boiler has detected an internal communication error with the gas control system, meaning it will not light because it cannot safely manage your fuel supply.

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

Fuel valve control 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.63View →F.64View →

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