I'm affraid you need a new heater.
Take approx 8 - 10 screws out of the metal cover on back of dryer. You will then see 2 screws holding heater to rear pannel. Remove these. Carefully pull heater wires though hole. 1 x red, 1 x white, 1 x black, 1 x yellow. Make sure you connect new heater wires the same. Job done. New heater should cost about £20.
Derek Hatfield Hoove/Candy service engineer, January 2009