[n0c7]

I just installed my brand new dryer in the basement. The floor is painted concrete. When I run the dryer I get a slight haze of moisture on the floor around the wall dryer duct opening/flex pipe connection. The dryer duct runs into an insulated drywalled wall and directly up to the outside. I cannot feel any air leaks and made sure all the connections are tight and that there are no tears in the semi-rigid connection pipe.

Is this just a reaction because the floor is so cold yet the vent is hot? As soon as the dryer is off the moisture almost immediately dissipates.

 

[gregzoll]

What you are seeing, is caused by heated air hitting cool air, which is dew point. You may want to check the humidity level in the basement, or living space. Too high, allows mold spores, etc, too low causes other problem. Should be within 50-60%.

 

[n0c7]

Humidity level in the room is within check. Basement floor is very cold to the touch however room temperature is about 22C(72F).

 

[gregzoll]

What you are seeing, is typical.

 

[n0c7]

Is there anyway to prevent it?

 

[gregzoll]

Try to spin a little more moisture out of the clothes. This effect happens with every dryer, due to you are talking about moist heated air, until the clothes dry. Also make sure that the vent is opening all of the way on the outside of the home, so that there is sufficient airflow for the dryer vent.

 

[n0c7]

So I guess my only really concern is if this will be a problem over time and cause the drywall and insulation to rot around that opening?

 

[gregzoll]

Not really. Only way the paper would rot, would be water dripping on it. There is no worry about it, it is typical behavior when venting a dryer. If it is a gas dryer, you tend to see this more often, but with an electric dryer, it is typical. I tend to make sure that my clothes are spun in the washer, so as not to be dripping wet when placing into the dryer. In all reality, check your humidity levels, because any moisture in the are, is causing the Dewpoint effect. Cool moist air, meeting warm air causes this, but again, no worry, because it is not damaging.

 

[n0c7]

Well after two months this is what it looks like:

This can't be normal. There has to be an air leak inside the wall. If I shove a paper towel between the drywall and floor gap after 20 minutes its fully saturated. The flex pipe is tight and no air leaks can be felt. The portion of the drywall that is stained it hot to the touch when the dryer is running but the rest of the area around the opening is not.

 

[gregzoll]

I would be looking at leaking drain pipe, or water pipes for the washer at this point.

 

[n0c7]

Doubtful - I saw this wall before it was drywalled and the plumbing pipes aren't near it.

 

[gregzoll]

Moisture is getting in there some way, and it is not coming from the dyer. What is above this space? Post pictures of the outside where this vent exits.

 

[Marty S.]

Disconnect the vent and look up the pipe in the wall with a mirror and flashlight. Bet it's not clean and the humidity is condensing and running back down the pipe.

 

[COLDIRON]

Turn the dryer on let it heat up go outside and make sure your vent is blowing hot air and the right volume. Your pipe might go in the wall and disconnected inside.

 

[gregzoll]

That is what I am thinking Marty & ColdIron. Either they are getting blow in from rain, as you both have said, either clogged vent or disco.

 

[REP]

My best guess is that the vent dosen't go all the way to the outside vent hood,or there is a big tear in that corregated vent pipe behind the wall where it gets hot. That needs to be fixed or it will cause mold and/or wood rot.

 

[n0c7]

Turns out they did not tape up any of the joints at the 90 degree elbow causing air leakage in and around the bottom plate and drywall opening. Air flow is fine, this is a new home without any blockages and I verified that nothing was disconnected when I opened up the wall.

Unrelated to the actual moisture issue, someone did puncture the washer drain with a drywall screw but luckily the screw was holding the water back. They also managed to damage the black wire of the 220V plug for the dryer as well as cut out a stud to make room for the washer drain.

Gotta love the surprises in brand new homes. :laughing: All fixed..

 

[gregzoll]

That is why I always double check and take time doing something. No need to rush. At least you hopefully got a lot of problems nipped in the bud, and there are no others to be found. Keep your fingers crossed.

 

[COLDIRON]

You really should get rid of that flex hose and run solid 4" metal pipe.

Too many lint traps.

 

[n0c7]

I'm on the fence about the flex hoses. A solid pipe gives people false piece of mind and the assume they do not need to clean it out(not to mention difficult to connect in tight spaces) compared to someone who regularly cleans the flex out every year or two. 90 degree elbows still trap plenty of lint regardless of hose type.