Internet searches for TDS62 are not very fruitful
Zanussi make a TD62 Tumble Dryer and this may be what you have - you didn't say the brand.
You do not say what caused you to replace the heater AND the thermostats but no matter.
It's possible that the new heater is defective or a wiring error was made during the repair work.
I think you know this - you have made a partial diagnosis already.
Good luck...
July 2015