Emergency Lockout
F.62 on Vaillant ecoTEC Pro / ecoTEC Plus

Your boiler has detected that the gas flame is not turning off when it should, which is preventing the system from running 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

Error with gas valve – switch off delay

What causes this fault?

This fault occurs when the boiler's control system detects that the gas flame is still burning even after it has told the gas valve to close. The most common reason is a mechanical failure within the gas valve itself, but it can also be caused by a faulty circuit board incorrectly sensing a flame that isn't actually there.

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.27View →F.28View →F.29View →

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