Emergency
F.62 on Vaillant ecoFIT Pure 418

Your boiler has detected that the internal gas valve is not closing correctly when it should, which prevents the unit from starting safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Fuel valve shut-off delay fault

Engineer required

This is a emergency 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.61View →F.63View →F.64View →

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