Can't light gas oven

[boilerbeasty]

I have a delonghi GSS601 gas cooker.
I turn the oven to maximum, light it, and hold the knob in - waiting for it to be hot enough to stay lit. Instruction book says this should take about 10 seconds.
But minutes later, it still won't stay lit.

Any ideas for fixing it ? It is typically some bit which gets greasy, or fails.

 

[Sleepyhead]

Thermocouple failed or not in the flame.

 

[boilerbeasty]

thanks for the reply. I'll let you know how I get on.

 

[boilerbeasty]

the thermocouple was in the wrong part of the flame. ideally the end of it should be in the tip of a blue flame from the burner, but it wasn't. I've moved it and it seems ok now.

cheers