Krunk4Ever! says that if you use dryer sheets you can extend the life of your dryer and prevent it from catching fire by washing the lint filter with hot soapy water and a brush once every six months.
While you might pick all the lint off after every load, fabric softener sheets can cause a waxy residue to build up on the lint screen. If you run a waxed up lint filter under the faucet, water beads on the surface. This barrier can cause the dryer fans to overheat and, in extreme cases, cause your domicile to burn down.
So if you use dryer sheets, wash and scrub the lint screen every six months to prolong the life of your dryer, and your family. — BEN POPKEN