How clean is your dryer exhaust?

[Nords]

(Cross-indexed under the heading "But... whaddya DO all day?!?")

An out-of-state shipmate rents her condo to a couple we've befriended. As tenants go they're not dangerous but they don't appear to have a lot of handyman experience and we get all the "How do we fix this?" calls. The condo is 14 years old, they're original owners, and they've rented it out for the last two years.

Last week's call was "It takes two cycles and over an hour for our dryer to do a load of towels." We went through all the troubleshooting questions and, yup, it sounded like their dryer exhaust was plugged. We had cleaned their dryer less than a year ago but we went over to take a look-- I figured 30-45 minutes tops.

While I was unloading our Shopvac exhaust-cleaning tools from the car my spouse scampered ahead into the garage, moved the dryer & hose, poked her hand in the exhaust pipe, pulled out a couple handfuls of lint, saw it was clear to its turn, and said "Hey Nords, I think we're done here!" But being a nuke I wanted to check both ends of the exhaust. I noticed that the pipe went back 18", turned down below the garage, and disappeared.

By the time I found the exhaust vent I'd gone from the front of the house to the back-- about 25'. The lot slopes away from the house (which is over a crawl space) so the vent was about 10' off the ground under the back deck. When spouse blew the Shopvac through the dryer connection I actually heard burbling water. Hmmm, probably not a good sign.

When I pulled the exhaust grille off the ~4"x18" ducting I saw a puddle of water. Then I looked into the crawlspace and noticed how badly the ductwork was sagging from the joist hangers-- it was full of water.

I went into the crawlspace along the ductwork and discovered that, with the exhaust pipe, it was more like 40' and three right-angle turns (down, along, and out). The ducting didn't rattle or sound hollow-- it was like knocking on a tree trunk.

So I broke the joint between the exhaust pipe and the ductwork. We fished the exhaust pipe at just over six feet, of which two feet was plugged solid. [Insert Three Stooges chimney-cleaning episode here.] The rest of the ductwork was full of 14 years of lint & water-- and, no doubt, stachybotrys. I ended up pulling about a third of the ductwork for show & tell and letting the six feet of dryer exhaust pipe just shoot down into the crawlspace dirt.

We sent a couple dozen photos to our shipmate, who's forwarded them to the HOA. The gated neighborhood has at least 100 units and a full-time manager who is probably not going to be my friend.

Hey, thefed, wanna spend the winter in Hawaii?

[honobob]

OMFG!

[FIREd]

Makes me glad that our dryer vents out directly through the wall behind it. We have less than 2' of ductwork to keep clean! On a side note, it looks like one of the cleanest crawlspaces I have ever seen!

[bbbamI]

Wow, looks like a dust bunny convention. I think I saw eyes!

[CuppaJoe]

Quote:

Originally Posted by honobob OMFG!

-
Hey, Hono, score one for renting over buying!

[samclem]

Wow! I think we covered this here recently, but long vent runs like that are prone to condensation on the inside (far less in Hawaii, I'm sure). It's especially bad when the pipe is in contact with a material of high heat capacity (concrete, wet earth). But even a long, straight run of pipe will frequently result in condensation on the inside of the pipe. The lint sticks to the water, gets matted, and builds up to dangerous levels. Wrapping the outside of the pipe with insulation can keep it warmer and more free of condensation.

It's amazing these folks didn't figure something was wrong sooner. And that they didn't have a fire.

[Khan]

Quote:

I went into the crawlspace along the ductwork and discovered that, with the exhaust pipe, it was more like 40' and three right-angle turns (down, along, and out).

I tend to wonder about the thought processes at the time of installation.

[Martha]

I can't believe that this was code.

[UncleHoney]

If I wanted to design a dust collector that would be a good start. Doesn't look like any thought went into that vent layout to me. The run is way too long and the large rectangular duct causes low air velocity and even more lint to settle out.


A little design criteria for dryer vents.

The Ultimate Dryer Venting Guide

[cute fuzzy bunny]

You probably dont want to leave the duct open in the crawlspace, or you'll get a nice growth of mold, mildew, rot and encourage bugs to live in the crawlspace.

I have a different method of keeping this from happening. Once a year I pull the dryer out and stick my 200mph leaf blower into the opening.

Our old house had the pipe go into the wall and then straight up and out the roof. Why that was considered a good idea when the dryer was on an outside wall and could have had a 6" horizontal pipe to the outside is beyond me.

Anyhow, first time I stuck the leaf blower on and fired it up I heard "whump clank" from above. I walked out front to see that the cap for the pipe had been blown off when the huge lump of lint shot up the pipe. It looked like it was snowing.

[Achiever51]

Quote:

Originally Posted by cute fuzzy bunny I have a different method of keeping this from happening. Once a year I pull the dryer out and stick my 200mph leaf blower into the opening. ... Anyhow, first time I stuck the leaf blower on and fired it up I heard "whump clank" from above. I walked out front to see that the cap for the pipe had been blown off when the huge lump of lint shot up the pipe. It looked like it was snowing.

Sounds like the plot for a new sit-com!! Bet your neighbors were amused!

[Martha]

Ask him to tell you about his experience dusting with the leaf blower.

[ls99]

From Nords post: 40' feet of pipe and 3 right angles. If memory serves a right angle duct piece is equivalent to about 25' of straight pipe. Nice work by installers, NOT. Glad you found it not me.
I clean dryer duct twice a year, it needs it. 8' long with 2 right angles. No horizontal runs.

[cute fuzzy bunny]

Quote:

Originally Posted by Martha Ask him to tell you about his experience dusting with the leaf blower.

That worked out great except for the gas exhaust smell. Should I ever be called upon to dust again, I'm planning on using the electric blower.

[FIREd]

Quote:

Originally Posted by cute fuzzy bunny That worked out great except for the gas exhaust smell.

And the carbon monoxide poisoning...

[cute fuzzy bunny]

Eh, wasnt a problem. I had the doors open. Where else would I blast all the dust to?

I do still lament the loss of several lightweight, breakable knick knacks.

[Gardnr]

Quote:

Originally Posted by cute fuzzy bunny I do still lament the loss of several lightweight, breakable knick knacks.

Do you.....do you really?

[cute fuzzy bunny]

Not really. That was way more effective than the trick I did with the laundry...putting a pair of my wifes fuzzy pink slippers in with a load of her black scrub pants.

We're not even going to talk about the dishwasher, other than to say it seemed quite reasonable to put things other than dishes in it.

[Free To Canoe]

Wow! This post makes my back hair stand on end! I am going to inspect my dryer duct thoroughly! I have been feeling that the dryer is not working quite right.

Like Khan says, It make you wonder about the thought process during installation.

Free to Canoe

[cute fuzzy bunny]

Common spot for professional arsonists to start a fire...the dryer duct...