dryerexhaust-vent
A few days ago our dryer started complaining about a blocked airway, so I went up on the roof to check out the vent and sure enough the screen was completely clogged with lint.
It's a new vent that was installed along with a new roof in November, so I imagine I'll have to go up there and clean it out every 3-4 months.
Is this really part of regular home maintenance? Neither my wife nor I recall our parents ever doing this sort of thing.
I cannot say I'm a fan of the design of that vent - although looking at your other question, I'm rather surprised that lint is falling down into that gap. Possibly your fan is creating too much pressure, and it's backing up inside the vent at the 180 and thus air is escaping through the pushing some lint down into that gap, where it can get stuck.
If that's the case, then you might try installing a baffle inside the vent to force lint up far enough in the vent so that it has to go out the intended port, but which still allows water out. Like so...
Sorry, the color doesn't show well, but inside I've added a piece of metal running from just below the intake port to nearly the end of the angled portion of the vent, with a brace connecting it to the body to keep it stable. You can't see it but there should be drip holes at the point where the new plate hits the flashing for water drainage.
The idea being, lint flies in and cannot be forced directly down to the gap in question, but water will hit the tray, run back and go through the drip holes.
That or replace it with this
As a general rule, dryer vents should be cleaned out with a brush (attached to a long chain or rope or flexible rod so they can be run through the duct) every 6 months or so. If the arrangement of the vents in your townhouse community is such that you cannot easily do this yourself, you should take it up with whatever owners association or management company there is overseeing the site, since lint clogged dryer vents can be a source of fires, which should be a concern far beyond the impact on your dryer's performance.
If you applied something like a leaf blower to the bottom of the duct, you may have blown the cap on the top right off it, which would add to your problems.
Best Answer
Your parents did not have a screen at the exhaust vent terminal either. Somebody installed the wrong type of vent cap on the dryer vent. Dryers are particularly dependent on much free flowing air for proper operation. All dryer exhaust air is full of fabric lint. Fabric Lint will always clog a screen. Either replace the existing cap with the right one, (screen free) or jerk the screen out of that thing and live happily ever after!