186. Troubleshootingnn Interference with and repairs to the hob MUST NOTbe carried out by unqualified persons. Do not tryto repair the hob as this may result in injury anddamage to the hob. Please arrange for repair by asuitably competent person.A crack has appeared in the hob surfaceDisconnect the cooker immediately from the powersupply and arrange for its repair. DO NOT use the cookeruntil after the repair.My hob is scratchedAlways use the cleaning methods recommended in thisguide and make sure that the pan bottoms are smoothand clean.Marks from mineral deposits from water or food can beremoved with a cleaning cream. However, tiny scratchesare not removable but will become less visible in time asa result of cleaning.The oven fan is noisyThe note of the oven fan may change as the oven heatsup – this is perfectly normal.Power failureIn the event of a failure in the electrical supply,remember to reset the clock to make sure that thetimed oven continues to operate.Food is cooking too slowly, too quickly, or burningCooking times may differ from your previousoven. Check that you are using the recommendedtemperatures and shelf positions – see the ovencooking guide. Then adjust the settings according toyour own individual tastes.The oven is not cooking evenlyIf you are cooking a large item, be prepared to turn itround during cooking.If two shelves are used, check that space has been leftfor the heat to circulate. When a baking tray is put intothe oven, make sure that it is placed centrally on theshelf.Check that the door seal is not damaged and that thedoor catch is adjusted so that the door is held firmlyagainst the seal.A dish of water when placed on the shelf should be thesame depth all over. (For example, if it is deeper at theback, then the back of the cooker should be raised up orthe front lowered.) If the cooker is not level, arrange foryour supplier to level it for you.The timed oven is not coming on when turned onmanuallyIs the power on? Is the clock illuminated? If not, theremay be something wrong with the power supply. Is thecooker supply on at the isolator switch?Has the time of day been set?The timed oven is not coming on when automatic cookingHas the oven knob been left in the OFF position bymistake?Oven temperature getting hotter as the cooker gets olderIf turning the temperature down using the oven controlknob has not worked, or has only worked for a shorttime, then you may need a new thermostat. This shouldbe fitted by a service person.