My Zanussi 1600 jetsystem washer dryer keeps stopping during the drying cyc?

My Zanussi 1600 jetsystem washer dryer keeps stopping during the drying cycle at random times, no error is reported, I have cleaned out all the fluff from the condenser etc, but the machine still stops during the drying cycle and resets itself back to zero time.
Can somebody please help

Thanks

M J