The better a dryer vent
blows, the less lint builds up in it. Short vents blow
better than long ones. Full size dryers blow better than
smaller stack dryers or older dryers. Vents with a lot
of turns and elbows blow worse and build up more lint.
Very short vents attached to full size dryers may never
need cleaning! Most vents, however, "Dryer Vent Cleaning
should be performed every six months to three years
depending on many factors such as dryer efficiency,
length of duct, number of turns in duct, length of any
vertical duct."
A plugged vent will
certainly cause a dryer to run hotter and increase the
chance that something could catch fire. A dirty vent,
however, is only one link in a chain of events that must
occur for a fire to start. Other events may include:
failure of thermostat and limit switches in the dryer,
lint inside the dryer, a missing or damaged lint screen,
and a crushed hose behind the dryer. Some of our
competitors employ "scare tactics" and reprint newspaper
articles about fires caused by dryers. Though fire
hazards may be exaggerated, many fire departments and
insurance companies do require that dryer vents be
inspected and cleaned regularly.