Dryer vents work by drawing in hot air and pushing the air through tubing connected from the dryer to an opening, which leads outside. These features are common for outside dryer vents; however, an indoor dryer vent does not run outside. It uses a filter attachment to dispel hot air.
Dryer vents are attached to the vent hood on the back of the dryer using tubing. On outside dryer vents, the tubing connected to the dryer travels under the floor or through a window where hot air and moisture are pushed outdoors by a fan inside the dryer. The vent helps prevent fire hazards that are caused by dispelled materials. The dryer vent also prevents mold from accumulating as a result of hot air and moisture lingering inside the home.
The design of indoor dryer vents is similar to outdoor dryer vents, however, indoor dryer vents do not dispel hot air outside through a window or under the floor. Indoor dryer vents are positioned next to the dryer and use a filter attachment connected to the end of the tubing. The attachment reduces the amount of hot air, re-circulates heat and captures discharge from the dryer that can cause a fire.