Emergency
F.88 on Vaillant ecoTEC plus System

Your boiler has detected an issue with the assembly that controls the supply of gas to the burner, meaning it cannot safely ignite to provide heating or hot water.

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

Gas valve 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.28View →F.29View →

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