Our dryer stopped working late last year. It took us about a week to fix it, because every time we thought we fixed it, we found out later that we were wrong. We thought the lint traps were clogged, so we vacuumed them out. Then, we pulled out the dryer and cleaned it out from the back, and pulled out a clog in the wall. Next, we went outside (after quite a snowstorm) to see if the vents were open. They were iced shut. We de-iced them by banging them with a broom handle. We went into the attic space above the garage and saw the vent hose sagging in between the joists. The next day, we prepared ourselves to drain them, only to discover that it was solid ice. We tried to shake the ice down, but the flimsy hose fell apart. The day after that, we went to get a new dryer hose and installed it, finally restoring order to our dryer. We also added 2x4s to keep it from sagging again.
What does icy lint look like? Absolutely disgusting.