make sure, if you use dryer sheets, that you wash it with soap and water,occasionally..a film tends to build up on the mesh..and stops the dryer from working the way it should.
with 3 teenage kids in the house,years ago..my husband had a big note attached to the dryer door:
"7 out of 10 house fires are caused by failing to clean the lint trap out after EVERY Load" (lint build up in the hose)