Ariston washer/dryer. Dryer not working

probably 2 separate faults

no heat is possibly either open circuit on the elements which are at the top of the machine, or open circuit thermal cut outs (up to 3 of) located
also at the top of the machine near to where the element is and along the flow of the hot air,

you can check these with a normal electrical multi-meter, unplug machine before testing

as for the vibration on spin, just look for any loose suspension legs, and or twisted drum alignment, very difficult to work on due to lack of access but sometimes just re-tightening the legs up etc, could cure the vibration

hope i have helped you to start somewhere

take care to note in detail any wires or parts removed or in case of accidental removal