Is my gas burner an FSD problem or a thermocouple problem?

[Gary M]

I am troubleshooting a gas hob where one burner is reluctant to light. When it is lit and I blow the flame out the FSD on that burner cuts off immediately, whereas the others take 5-10 seconds as normal. I have tested the thermoucouple for continuity and also some sort of mV output (when held over a candle!). Do you think this is an FSD problem or a thermocouple change?

 

[Chuck]

I think it's a problem that needs a Gas Safe Registered engineer to fix it.

 

[Gary M]

Thank you for keeping me safe. If it is the FSD then I agree I need a gas safe engineer! However I have now sourced a new T/C and will see if changing that solves the problem.