Dryer Vent Cleaning: Clothes Dryer Lint Fire Hazard

Clothes Dryers Cause House Fires
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A clothes dryer doesn't look scary or appear to be too dangerous. Unfortunately, it is the cause of over 20,000 house fires every year totaling millions of dollars in damage. Regular cleaning and maintenance can protect your family and your investment in your home.

Get Rid of Dreaded Lint In The Dryer

Whether you use an electric or gas clothes dryer, you will have lint. Lint builds up in the lint trap but also inside the dryer hose and vent and can reduce air flow and drying efficiency.

Lint can cause humidity levels to rise around vents causing mildew and mold to develop in walls and insulation. But most important to remember: Lint is combustible. Lint causes fires.

Fortunately, removing dangerous lint is simple. The first area to clean is the lint trap. It should be cleaned after every load by removing the lint from the screen and wiping the edges. If the screen seems clogged, it may be front the dryer sheets you have been using. Submerge the lint screen in a sink of hot water and then scrub with a bristle brush to remove all the built-up fabric softener.

The key to success in de-linting a dryer is a dryer lint brush. This long-handled flexible brush will help you reach areas that you cannot get to by hand.

Remove the dryer lint filter. In the opening - whether on the top of the dryer or inside the door, use the brush to gently loosen the built-up lint. Don't force the brush if you meet resistance but be sure to cover every surface as much as possible.

Remove the big chunks of lint that come out with the brush. Don't worry about the smaller pieces.

Replace the lint filter (which I'm sure you have cleaned). Turn the dryer to air only and run for a cycle. This will pull the lint into the filter or blow the loose particles out the outside vent.

Get Rid of Dreaded Lint In The Dryer Vents

At least once per year, unplug the dryer and check where the exhaust vent connects to the dryer.

The hose or pipe is held in place by a clip or a steel clamp that can be loosened by pliers or a screwdriver. After removing the pipe, reach inside the dryer opening or use a vent brush to remove as much lint as possible. A shop vacuum is handy for removing the most lint and use a damp cloth to wipe away remaining lint around the connection. Then  look inside the hose or pipe and clean it as well.

If you still have a white or silver vinyl duct hose, it should be replaced immediately. It is flammable and if ignited by the dryer it will burn and cause a house fire. All national and local building codes now require metal ducting for clothes dryers. Ideally, you should use rigid aluminum tubing pieces between the dryer and the outside vent. This type of tubing does the best job of resisting the collection of lint in the duct. Flexible aluminum ducting is available, however, it is more prone to collecting lint inside.

One last step is to clean the exterior vent. Again remove as much lint as possible using your hand or a shop vacuum. You may need a screwdriver or another tool to hold the vent flap open for easier cleaning. If you live in a high humidity area or use your dryer more than twice weekly, you may need to clean this vent several times per year.

Use the Dryer Safely

If possible, clothing that has been soiled by volatile chemicals like gasoline, cleaning agents or even large amounts of cooking oil should not be dried in a clothes dryer. If they must be dried in the machine, wash the clothing more than once to minimize the risk of fire. Use the lowest heat setting and shortest drying cycle possible. Use a cycle with a cool-down period at the end of the cycle to prevent ignition.

Install the Dryer Correctly

A clothes dryer should not vent inside your home or attic. The exhaust contains too much humid air and can cause problems with mold and mildew which are hazardous to your health. A ventless dryer should be used if outside venting is not possible.

The maximum length of a clothes dryer exhaust duct should not exceed 25 feet from the dryer location to the wall or roof termination.

The maximum length of the duct shall be reduced 2.5 feet for each 45-degree bend, and 5 feet for each 90-degree bend. The maximum length of the exhaust duct does not include the transition duct.

This means that ​dryer ducts should also be as straight as possible and cannot be longer than 25 feet. Any 90-degree turns in the duct reduce this 25-foot number by 5 feet, since these turns restrict airflow.

Be certain that you have a 220v grounded electrical outlet available for an electric dryer. A professional should always be hired to install gas lines for gas dryers.

Never store volatile chemicals or rags near a dryer. Some liquids emit vapors than ignite. The area around the dryer should be kept free of lint, papers, and stacks of clothing.