Why You Need a Vent
To understand how the dryer vent works, you first need to understand what is happening to the air inside your dryer. The air is pulled in and heated by electric elements, then sent through the clothes and pulled out by a fan and into the vent. The air travels down the vent to the outdoors. If you didn't have a vent on your dryer, all that hot air and moisture would be forced into your house where it can cause mold and rot, not to mention high air conditioning bills. You can get the same results if the vent ends up getting clogged somewhere along it's path to the outside.
How the Vent Works
The dryer vent is hooked to the vent hood located at the back of your dryer. The tubing used to vent your dryer should be made from aluminum. Many of the old vinyl or plastic tubing is no longer used due to fire hazards and changes in the building codes. The tubing then goes from your dryer under the floor in a crawl space or in a wall to the attic where it is fed to the outdoors. Flexible aluminum elbows and foil tape are used to connect all the tubing. Then a cover is usually placed over the end of the tubing to prevent the heat and moisture from going right up to your roof or damaging an outside wall. The cover helps to disperse the heat and moisture in several directions. All dryer vents should take the shortest route to the outside.
Cleaning the Vent
Keeping the dryer vent clean is important to the efficiency of your dryer. If lint gets through the trap, it can slowly clog the vent, preventing the hot air and moisture from leaving the house. This can cause the dryer to work harder and take longer to dry the clothes, resulting in breakdown of the dryer and higher electric bills. Cleaning the vent is simple if you can get to it. You can take it off, clean it out with a rag, and put it back on. However, if the tubing is running through your walls, it may not be that simple. If you know you have a straight tube from the attic, you can attach a brush to a rope and let it down into the tube. It will pick up the lint, but you won't be able to get out a clog. If you don't know how the tubing is run, it is better to hire someone who does this for a living. You could dislodge an elbow and then have a real problem on your hands. The vent should be cleaned out at least once a year. This can save you many headaches and save on your bills.