Replacing an existing dryer vent follows the same steps as outlined above, along with the added step of removing the damaged or non-sealing dryer duct first. To remove a dryer duct, begin by unplugging the dryer if it is electric, or turn off the supply valve if it is a gas dryer. Then, carefully pull the dryer away from the wall to give yourself some space and disconnect the dryer duct from the back of the dryer. If you used vent clamps to secure the dryer vent, you may need a screwdriver to help you disconnect.