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During the normal process of lint is caught in the lint trap while the air is expelled through the system. If there are obstacles in this system, which would mean the airflow is restricted and therefore get your dryer has to work overtime to get free. The entire process is still here, the engine may overheat and cause a dry fire.
Unlike most other materials that can be found at home of lint is highly flammable and cause a fire in a very short time. If we are not careful the fire can spread and generated more than your house and put the lives of people and materials at great risk.Dryer Vent Cleaning