Try drying the clothes with the duct disconnected from the back of the
dryer. A pair of pantyhose will temporarily contain the lint. If the
dryer works well, then it is your dryer vent that is clogged or
damaged. This can cause the thermostats to fail or heating elements to
burn out. Call a Certified Dryer Exhaust Technician or DIY.
Alisa
Certified Dryer Exhaust Technician
http://www.CleanYourOwnDryerVent.com/