Smell gas? Leave the property and call the National Gas Emergency line on 0800 111 999

F.62

Vaillant fault code

Vaillant F.62: the flame went out later than expected after switch-off

Engineer only

When the boiler turned the burner off, the flame took too long to go out. Vaillant lists a leaking gas valve or faulty electronics.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to: ecoTEC plus. Codes can differ between models, so check your manual.

From Vaillant's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

Model	Meaning	Causes listed for engineers
ecoTEC plus	Gas valve switch-off delay fault	Delayed shutdown of gas valve, delayed extinguishing of flame signal, gas valve leaking, electronics defective

Can I keep using the boiler with F.62?

Leave it off. A delayed flame switch-off points to the gas valve and needs an engineer.