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Why Dryer Fires Occur Lint accumulation and reduced airflow feed on each other to provide conditions ripe for a fire. Lint is a highly combustible material, which, interestingly enough, is one of the ingredients in a recipe for home-made fire starters. A number of dryer vent problems contribute to this. A growing problem Traditionally, most clothes dryers were in the basement. However, nowadays many newer homes tend to have dryers located away from an outside wall in bedrooms, bathrooms, kitchens and hall closets. These new locations mean dryers tend to be vented longer distances and vents are generally installed with sharp turns and bends to accommodate the structure of the home. As a result, dryer vents are harder to reach, and also create more places for lint to gather. The ideal solution is to have short, straight, dryer duct venting. However, a dryer vent booster, while not the ideal approach, can improve your dryer venting in cases where your venting is longer and/or has more bends than it should. In addition to creating a fire hazard, if the venting is too long and/or has two many bends, it will cause your dryer to take much longer than necessary to dry loads.
Inside the Dryer Lint is the biggest culprit here. As you know from cleaning out your lint filter, dryers produce very large quantities of lint. Most people assume their lint traps catch all the lint, and that all they need to do is clean them out after each load. However, a significant amount of this lint is not caught by the lint trap and builds up inside the dryer-even on the heating element! If you are skeptical, try this experiment: pull out the lint trap and look underneath it- you may find large mounds of lint staring at you. Lint can build up on the heating element and in other places inside the dryer, causing it to overheat and possibly catch fire. As a rule, a fire starts from a spark in the machine. However, improper clothes dryer venting practices outside the dryer can play a key role in this process.
Outside the Dryer There are many improper dryer vent practices which restrict airflow and lead to lint buildup, the two main preventable causes of dryer fires. Some of the most common and important dryer vent mistakes are: 1. Dryer vents are too long and/or have too many bends, but don't use a dryer duct booster, resulting in lint buildup. When it comes to dryer vents, shorter and straighter is better. 2. Use of flammable, flimsy plastic or foil duct extenders. Only metal vents should be used, which is what most manufacturers specify. Metal vents also resist crushing better than plastic and foil, which allows the air and lint to be carried out of the system. Reduced airflow from build-up or crushing can cause overheating and wear out the clothes and appliance faster. In fact, many state and local municipalities have placed requirements on new and remodeling projects to include all metal dryer venting. 3. Inadequate clearance space between dryer and wall. Many people create problems by putting their dryer right against the wall, crushing the venting material in the process. The cumulative effect of reduced airflow and the resulting lint build-up prevent the dryer from drying at the normal rate. This causes the high temperature limit safety switch to cycle on and off to control the heater. Most high temperature limit safety switches were not designed to continuously cycle on and off, so they fail over a period of time. 4. Failure to clean the dryer duct.
