Signs your dryer vent is blocked

A dryer works by pushing hot air through wet clothes and then pushing that now humid air out of the house. If the second half of that sentence stops working properly, everything else about the machine starts to look broken.

Lint is what stops it. It rides along with the air and settles wherever the line bends, narrows or gets crushed. It builds slowly, so the symptoms arrive slowly too, which is why they are easy to explain away one at a time.

Put the dryer on and walk outside to the hood. You are looking for two things. Is the flap or damper open, and can you feel a decent push of warm air coming out of it?

A damper that stays shut, or a weak trickle of air where there should be a steady push, means the line behind it is restricted. Lint caught around the hood itself is the same story from the outside.

Pull the dryer forward far enough to see the flexible hose at the back. Two problems are common and both are visible in a second.

The first is crushing. If the machine has been pushed back hard against the wall, the hose gets folded flat behind it, and a flat hose carries very little air. The second is the type: a thin foil or plastic accordion hose is worse at both airflow and lint than a rigid or semi-rigid metal one.

Clearing the line means the whole run, not the first accessible stretch: the transition hose, the takeoff where the line leaves the room, every bend, and the hood and its damper at the far end. The bends are the point. A line cleared up to its first elbow will be blocked again quickly, because the elbow is where the lint was.

The last step matters as much as the first: with the dryer running again, check the hood outside and confirm air is actually leaving the house.

Lint is flammable and a blocked vent line is worth dealing with rather than living with. Anyone who attaches a guarantee to cleaning it, though, is selling you something other than the cleaning. A clear line is a clear line, and that is the honest version of the claim.