Emergency
F.67 on Vaillant ecoTEC plus Regular

Your boiler's electronic control system is failing to correctly detect whether the burner is lit, so it has safely shut down to prevent gas from building up.

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

Flame detector input signal is outside the limits (0 or 5 V)

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.62View →F.63View →

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