Creda condenser tumble dryer thermostat problem?

I have a problem with my Creda Condensor tumble dryer...due to us not cleaning the condenser unit often enough the thermostat has blown. I have replaced the 2 thermostats (ive done this in the past and had no problems...) when I replaced them this time the dryer was very noisy and when I opened the door midcycle it was extremely hot and the clothes were steaming.
At the end of the cycle the clothes are still wet and the dryer doesnt seem to be heating again.

Could anyone assist?

Rich
March 2010