We've had the cooker for nearly 18 months; main oven used at least 3 times per week.  Now the gas to the oven is failing to remain alight.  Although it lights up as normal it goes out as soon as the control knob is released.  All other parts ie the other (smaller) oven, the grill and the hob are working fine.

Kitchen Ranges - New World - Spirit 100 (Gas) Kitchen Range