Pat
I recently fixed my mother's elderly Creda with the same issue. It's probably the Thermal Overload Cut-off device. This is located above the heater element at the rear of the machine. If you take the back plate off the machine you should be able to locate the heater element & the TOC should be secured by a screw above it and have a couple of connectors attached to it. Pull the connectors off and detach the part. You will be able to get one from a good domestic appliance repairer/parts stockist. Make sure the rating is equivalent or less than the one you have e.g. 110, 120, 135.
If that doesn't look burnt out, then it could be the element. This too, should be easily detacheable & you can get them on the web, e.g. diyitnow.co.uk.
Good luck!
Jools
Julian Ansell, July 2004