The answer to 'dryer vent smells bad' is that a smelly dryer vent is typically caused by lint buildup, mold growth, or a clogged vent. This can lead to poor airflow, which causes the vent to smell musty or like rotten eggs. The symptoms include the smell, reduced drying efficiency, and potential fire hazard.
To fix a smelly dryer vent, you can try cleaning the vent yourself by disconnecting it from the dryer, using a vent brush or vacuum hose to remove lint buildup, and ensuring the vent is clear and properly vented to the outside. However, if the smell persists or you're unable to fully clear the vent, it's best to call a professional dryer vent cleaning service to inspect and thoroughly clean the vent for you.