Hi there, it sounds like it could be your thermostat. I had the same problem with my ctd00 . There will be 2 thermostats which are located at the back of the dryer in the round shape. They look like 2 circles that will be screwed in. If they are raised/popped they have definetley blown and will need to be replaced. They should cost about £15 for both maximum(try ebay for cheaper still)
It could be the heating element, (which was the case with mine) when you check the thermostats you will see the heating element it has 2-3 black coloured bars with silver stuff going in front of it. have a close look if thebars look broken or cracked it will need replaced. it will cost about £35 it will come with 2 new thermostats too.
You will also need to clean the filter at the bottom of the condenser rinse under water to ensure all the muck is out.
I would try this first before you buy anything for it.
Hope this helps and sorts out your dryer
Good Luck!!!
Donna
donna paterson, April 2008