First, you should have had a move in inspection report or clause that they have 3 days to report anything non-functioning or damaged. Second, you should have had a clause that appliances are loaned not leased.
Finally train your tenant. Offer to remove the old dryer so that they can use theirs. Even have it changed out for them. My guess is that it an electric dryer and the heating element is all that is bad(inexpensive to replace)
"Appliances or furniture in the unit at date of lease per the attached Exhibit "A", are loaned, not leased to Tenant. Maintenance of appliances or furniture is the responsibility of Tenant who will keep them in good repair. "
Tenant agrees to accept said dwelling and all of the
furnishings and appliances therein as being in good and satisfactory condition unless a written statement of any objections is delivered to Landlord within three (3) days after resident takes possession. Tenant agrees that failure to file such statement shall be conclusive proof that there were no defects in the property. Tenant agrees not to permit any damage to the premises during the period of this agreement to woodwork, floors, walls, furnishings, fixtures, appliances, windows, screens, doors, lawns, landscaping, fences, plumbing, electrical, air conditioning and heating, and mechanical systems.