Smeg Gas hob cannot keep flame ?

Hi it is your thermocouple. I had the same problem. You have to remove the knobs on the front of the oven with an Allen key. Then gently pull off the press buttons for the timer unit. Remove the front panel. Then take off the top plate and unscrew the retaining bolts for the hob tray. This will then lift off. You will see some wires between the ignition points and the control panel. Unscrew the one that is not working and replace it. These cost about £5 from a smeg parts supplier.
I have replaced mine and gad no problems since.
It is a bit of work and is fiddley but actually very easy to do. Just need simple tools.

Good luck.

Mark
February 2011