Emergency
F.62 on Vaillant Combi Compact 242EB

Your boiler has detected a safety issue where the gas valve is not closing properly, which could mean gas is leaking into the burner when it shouldn't be.

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

Defective gas valve closure mechanism

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.27View →F.28View →

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