Dryer Vent Under House

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New dryer coming. My vent goes down into the crawl space. Make a 90 degree turn. And then runs out 6 ft to the outside. The vent cover broke so it is easy to see in the tube with flashlight. I run a log pole through and it goes all the way through. I can see all the way out the other side. I don't think the guy who did the work ever hooked it up.

So for the past 11 years, I think (don't know) that this has vented under the house. My house under pinning is made with 1x4 inch pine boards gapped one quarter inch. I want this house to breath and there is a ton of air flow beneath it. The crawl space is also about 30 inches so plenty of room. I wonder if I can just let it vent to the crawl space since I have so much ventilation.

Thoughts? Suggestions?
 

bud16415

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First off welcome to the forum. :welcome:


This is just my opinion and others may disagree. I don’t think you will do any great damage letting it vent below the house and it seems that has been what has been going on for a long time.


Is there no way to direct the vent across the room and out higher off the ground? A low vent like you have and one with the cover missing is an invitation for critters to come in.


Personally I would want it hooked up and venting outside the house just because I wouldn’t want the lint and such building up in the crawl space. You do have to keep those lines cleaned out though.
 
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First off welcome to the forum. :welcome:

Is there no way to direct the vent across the room and out higher off the ground? A low vent like you have and one with the cover missing is an invitation for critters to come in.
Thanks for the welcome and the quick reply. There is no way to do that, but I will put a vent cover outside no matter what. I suspect that flexable hose behind the dryer is stopped up. Hate those. and no easy way to get to it. You have to pull the washer out. Then move the dryer over and pull the dryer out.
 

Jeff Handy

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You should pop a new hole right behind the dryer to the outside.

Post some pics of the laundry room, and of the outside wall behind it.
If it is an outside wall.

Otherwise, get down under and connect that vent properly.

The heavier foil flex vents are ok at the dryer.
The flimsy ones over a wire frame slinky are dangerous.

Even bricks or siding are not that big a deal to make a new vent hole through.
A short vent line will dry clothes faster.
And less chance of fire from lint build up.
 
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You should pop a new hole right behind the dryer to the outside....

The heavier foil flex vents are ok at the dryer.
The flimsy ones over a wire frame slinky are dangerous. [\QUOTE]
Thanks for tip on the heavier foil flex vents.

Unfortunately, it is an inside wall. It is also very close to the electrical panel.

Keeping it clean is going to be tuff. I wonder if I can rig a connection from the pipe to my shop vac and just vacuum it on occasion. Not sure what that connection would be. Maybe stuff around the shop vac with foam and duck tape it.
 

bud16415

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Your dryer sounds like mine shoehorned in.


Mine vents exactly like yours only I have an open basement below. I go down there and pop the 90 off and clean both vertical and horizontal at least once a year. If you have a crawl space I would suggest a access panel to get back in that 6’ to do the same. Or do as I suggested and run across that back wall and out the same side just higher. You need a plan that allows it to be maintained somehow. Just blasting it under the house is not best but likely better than a clogged up run.
 

Jeff Handy

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If the vent under the house is solid metal, you can get a dryer vent cleaning kit.

It has sections of short flexible fiberglass rods that screw together as long as needed, up to about 16 feet, some are longer.

A bristle brush threads onto the end.

It can bend around elbows.
Sometimes you have to shorten the brush end.
Or trim it so it is not as fat.
Don’t try any motorized or rotating types, not needed.

You can access the vent from both ends to poke stuff loose.

Then run the dryer to blow out the loose stuff, or blow with a shop vac, or shove in the vac hose and vacuum.

I have also used a long ribbed 1 1/2 plastic hose used for pool vacuuming.
They come as long as 25 feet.
Shove it in there while blowing or vacuuming, attached to shop vac.

If the vent under the house is all flexible, you will have to just try blowing it clean with the shop vac.
 
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The straight run is sold metal and looks clean as a whistle. Why wouldn't it be if it never got hooked up. Seems to me there should be a pipe coming down with an elbow. Than this should be attached to the elbow. Should not be able to see all the way through it. It also seem longer than 6 foot so I am thinking it never got connected.
 

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I apologize if I’m repeating others thoughts in this. I haven’t read all the replies.

My immediate thoughts are that you are adding a ton of water under your house and into your crawl space. My guess is that it was previously hooked up but because you can’t use screws to fasten dryer duct you rely on tape to hold it together. If they didn’t support the pipe properly then the metal foil tape that is supposed to be used can heat up and fall apart. If they used duct tape then it never had a hope to begin with.

If you see any lint outside on the ground then it was probably discharging outside up until quite recently.

You may be able to reconnect it by having one person inside reaching through the vent from inside and one person outside maneuvering the pipe from outside. Together you can get it to reconnect then use one button head screw, or something that will not create a lip for lint to catch and build up on, screwed from the inside just to hold it together since there is clearly no strapping to hold it up in place. Depending on how it holds together you may be able to “glue” the connection instead of using a screw by using high temp silicone between the two pipes. It would only be for fastening purposes not for sealing so no need to run a bead on the inside. You just want to hold it together well enough so that the washing machines crazy spin cycle doesn’t cause it to break loose again as it thumps across the living room.

Don’t use anything flammable to attach the duct together and do not screw into the pipe from the outside because the protruding screw will cause the lint to block up in no time flat. Do not tape it together from the inside either.
 
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Your dryer sounds like mine shoehorned in. ...

You need a plan that allows it to be maintained somehow. Just blasting it under the house is not best but likely better than a clogged up run.
Yes it is. I have a guy coming out Saturday to connect it. That's all he does. Clean dryer vents. Once he does his thing, I was wondering if I could create a seal on the smooth wall pipe to the shop vac and then while running turn on the vac. It would be blowing from one side and sucking from the other. Not sure if that would prevent any clog or just make a clog harder to get out.

Maybe every couple of years I have him come out and remove the washer and dryer and clean the dryer and then the vents and put it back. Hate to do that. Always afraid he will scar my wood floors or not get a washer connection secure or something.

Maybe a better plan is have him disconnect the pipe underneath and use a flexable brush up through the flexable hose. I guess he will know when he gets here.

Anyway you can see why I thought... Just let it go under the house. House is vented like crazy and there is a constant breeze under there.
 
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I apologize if I’m repeating others thoughts in this. I haven’t read all the replies.

My immediate thoughts are that you are adding a ton of water under your house and into your crawl space. My guess is that it was previously hooked up but because you can’t use screws to fasten dryer duct you rely on tape to hold it together. If they didn’t support the pipe properly then the metal foil tape that is supposed to be used can heat up and fall apart. If they used duct tape then it never had a hope to begin with.
Thanks for this. I recall the company sent a very young man not much out of high school if that. I always prefer someone seasoned. Your explanation makes sense to me.

I hear you on the moisture. I was hoping the ventilation took care of that. Like I say, the underpinning is 1/4 plank with a quarter inch gap between each plank. You can feel the breeze blow from one side to the other.
 

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Thanks for this. I recall the company sent a very young man not much out of high school if that. I always prefer someone seasoned. Your explanation makes sense to me.

I hear you on the moisture. I was hoping the ventilation took care of that. Like I say, the underpinning is 1/4 plank with a quarter inch gap between each plank. You can feel the breeze blow from one side to the other.
And it probably would be fine for a long time. But on really humid days the moisture would have little motivation to vacate. Since the wood underneath is not treated lumber it’s best to not introduce additional moisture if you can avoid it. With that said, there are exceptions for everything. But the safest thing to do would be to reconnect it, and it sounds like that’s what you are doing.

Sometimes the young guys are eager to get the job done and put more effort into their work than the seasoned guys do. As long as they know the do’s and don’ts then their work should be ok provided they like their job and have a good work ethic.
 

Jeff Handy

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The metal foil tape is good stuff.

Extremely sticky, wrap with multiple layers, but you might need to clean duct surfaces with windex or bathroom cleaner first.
Solid pipe duct is often oily.
And old ducts are probably loaded with caked on dust.

Foil tape is great to stabilize adjustable elbows too, wrap it all around once you have the elbow just right.

Screws are not needed or advisable.
Stainless steel hose clamps approx 5 inch size will hold any male/female connection.
Or use foil tape, or both.

Screws will catch lint, and will snag the cleaning brush or a vac hose stuck in there.

You can use a coil of pipe strapping to hang ductwork from framing.
Add some foil tape around it.

Be careful, foil tape can cut your hand while you are smoothing it down!

And don’t use the flimsy aluminum elbows or connectors, galvanized steel is much better.
 

Jeff Handy

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In the crawlspace, making a long sweep 90 elbow from two adjustable 90 elbows cuts down on air friction, and helps the fiberglass cleaning rods to more easily bend going through there.
 

pjones

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The metal foil tape is good stuff.

Extremely sticky, wrap with multiple layers, but you might need to clean duct surfaces with windex or bathroom cleaner first.
Solid pipe duct is often oily.
And old ducts are probably loaded with caked on dust.

Foil tape is great to stabilize adjustable elbows too, wrap it all around once you have the elbow just right.
Yeah. I didn’t express this very well in my first post. Foil back tape is the industry’s standard for dryer runs in this area. Not to be confused with silver insulation tape that is foil tape with finer reinforcements, sometimes on a paper based backing. The correct foil tape has an acrylic based adhesive that manages time and temperature very well. Foil tape is literally foil with a clear glue attached and a peel back tape to expose the adhesive. It is easy to make a clean looking rip when it’s on the roll but once it’s on the pipe you will be hard pressed to pull it apart by hand. Given heat and time though and it will eventually slip so the pipe still needs to have supports under it to keep it suspended and in position. This pipe sees more abuse than the others so make sure it is fastened well and secure. If you have access to the crawl space and can access the vent then it is best to repair the pipe from there so it can be supported correctly and secured properly.
 
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