[BE911SC]

My home's laundry is upstairs, second floor. Vent goes into the wall, makes a 90 and drops straight down 15 feet or so under the house (no basement), makes another 90 and goes about 20 feet to the wall where it vents outside. I have a coiled up section of 3" plastic hose that I connect to my industrial portable shop vac, feed the hose in from the outside wall and suck out a huge lint ball every six months or so. I also feed the 3" hose down from the top. My clue for needing to clean it out is that laundry starts taking longer to dry. High-end house built in the mid-1980s, not jerry-rigged. Coincidentally, the dryer just croaked after ten years so another gets delivered on Sunday.