The answer to 'why is my dryer vent dirty' is that a dirty dryer vent is a common issue caused by lint buildup. Over time, lint and debris from clothes can accumulate in the vent, restricting airflow and causing the vent to become clogged and dirty. This can lead to longer drying times, higher energy bills, and even a fire hazard.
Some common symptoms of a dirty dryer vent include clothes taking longer to dry, the dryer getting hotter than usual, and visible lint buildup around the vent opening. To solve this, you'll need to clean out the vent regularly, either by yourself or by calling in a professional vent cleaning service.