Condensation accumulating in dryer vent.

luckie_reubs · 12-30-2008, 11:10 AM

Our W/D is on an interior wall of a single story house. The house is on concrete slab for foundation.

Recently we noticed that the dryer was taking longer to dry, and I discovered that there was a water build-up in the actual vent line. Ultimately, I had to run a plumber-snake from the outside vent to the inside starting point, duct-tape a towel to the end, and then pull the towel back through to absorb the water.

The dryer is now working better, but I fear that this was condensation and not rainwater (I assumed rainwater initially b/c one of the flaps on the dryer vent was missing and we've just experienced lots of rain).

Does anyone have a solution to this problem, or am I stuck with the snake and towel method until we move to another house after we outgrow this one?

yuri · 12-30-2008, 07:27 PM

Is it a gas dryer? They may give off more moisture than an electric. Try phoning some appliance repair companies in your area and see if other people have the same problem/ask them for advice. Don't know where you are but if it is very humid then that may contribute to the problem.

Good Luck

luckie_reubs · 12-30-2008, 09:41 PM

We're in south Alabama, and no, it's an electric dryer. Thanks for the info; I was just curious if there was anything I could do myself, or if anyone had any suggestions.

hvaclover · 12-31-2008, 12:45 AM

How is the dryer vent run?

luckie_reubs · 01-01-2009, 04:34 PM

The dryer vent is run underneath the house through the slab (I assume). One thing I do know, though, is that the vent does not go directly outside. It goes about 30 feet from the point of origin to the point of exit. I just noticed about 20 minutes ago that I'll have to do the same procedure again in order to avoid running numerous dryer cycles. Thanks for any info!

hvaclover · 01-01-2009, 04:36 PM

Your getting ground water seeping in.

Chemist1961 · 01-01-2009, 05:10 PM

Just puzzled here by your comments about loads still taking longer to dry. While I understand the issue with moisture in the pipe, I would approach that by replacing the existing vent with one with a weighted damper.
However if your dryer is running longer cycles in AUTO mode, you may have a secondary issue beyond the moisture in the vent. My dryer senses humidity in Auto mode.
If you have a partial obstruction in the exhaust of the dryer, humiditiy could also be building in the pipe at the blower within the dryer from lack of air flow as well as in the within dryer drum delaying the normal cycle shut off time.
Several years ago I had this problem when one of my kids pulled the lint screen and dropped fabric softener sheets into the lint trap area. We didn`t see them and put the screen back at the bottom of the drier door area. The blower sucked them into the exhaust pipe in the base of the drier and the blockage caused the drier to run continually for several hours in auto mode due to humidity staying in the drier.
When we switched to manual timed cycles the issue continued. The drier built heat, but the loads still weren`t drying properly. I cleaned out half a box of fabric sheets in the pipe and a ton of lint as well and the drier was fine after that.

luckie_reubs · 01-01-2009, 09:38 PM

Chemist: thanks for the response; hvaclover: I hope not; previously the water was clear, thus my assumption that it was condensation. I also checked the water meter, and there's no indication that there's a leaky pipe anywhere. Chemist: after clearing the water out on Sunday via siphoning and then a plumbing snake, the dryer ran beautifully. Tonight, I heard the sound of lapping water again, so I went back out with my hosepipe to start siphoning again. I don't think there's a blockage in the vent line b/c I ran a snake and a towel through on Sunday night with no problems. Tonight I shortened the vent connector (I don't know what it's called) that goes from the dryer exhaust to the vent line, and I pulled the dryer away form the wall. There is currently no binding at all in the vent connector, so air should be able to flow out easily and unimpeded from the dryer to the vent line. I'll keep an eye on out, and I'll post back. Thanks again for your help, and please let me know if there's any other info needed! BTW, Happy new year!

hvaclover · 01-01-2009, 10:44 PM

Slabs hold water and if you have cold winters the heat from the dryer can melt FROZEN GROUND WATER. Ground water does not have to dirty.

I have serviced enough in-slab ducts systems that act exactly as you describe. Some times it was a high water table. Sometimes a leak before the water meter so it would NOT register on your water meter.

Also possible to be on your meter side if the leak is too small to register mass flow.

My thought are NEVER SAY NEVER just solve it.

luckie_reubs · 01-02-2009, 08:58 AM

Quote:

Originally Posted by hvaclover

Slabs hold water and if you have cold winters the heat from the dryer can melt FROZEN GROUND WATER. Ground water does not have to dirty.

I have serviced enough in-slab ducts systems that act exactly as you describe. Some times it was a high water table. Sometimes a leak before the water meter so it would NOT register on your water meter.

Also possible to be on your meter side if the leak is too small to register mass flow.

My thought are NEVER SAY NEVER just solve it.

Thanks for the information. This is a 10 yr old house that we just purchased in Sept. 08. Is this something the inspector should have noticed or something that should have been pre-existing to this point? I know a few homebuilders in the area, and I'll chat with them about who to find in town to service this thing. Thanks again!

gregzoll · 01-02-2009, 11:28 AM

Can you run it up, and place a Roof Dryer vent on the roof, and vent up, not down through the slab? That may be the better solution at this point.

2G's · 03-07-2009, 12:32 PM

luckie_reubs,

Would be interested if you discover a solution. I have exactly the same problem you describe. In fact, I live in a relatively new townhome community (3 years old) and approximately 6 of 22 units have the same problem. All townhome units are on concrete slab, and the dryer exhaust travels either through or below the slab some 15 to 35 feet depending on the unit. Several of us began noticing a musty smell coming from the lint vent in the dryer, and clothes taking too long to dry. After further inspection, we all had condensation build-up in the exhaust pipe; some with significant water build-up that was wet vac'd out. One of the affected owners bought a new dryer with increased blowing power. He claims the increased air-flow power keeps the condensation from building up. I have been looking into a "dryer fan booster" but am not sure where I could attach it because our exhaust system is inaccessible underground and the manufacturer says you should not attach it within 15 feet of the dryer; closer to the other end the better. Suppose I could try to attach it to the outside end; but still looking into it. If you discover a permanent solution, please post. Thanks.

kenmac · 03-08-2009, 09:17 PM

Like the other poster said. ground water or condensation build up from that vent being under ground / slab... If possible , Re-rout the vent..I think that will solve your problem

diyme · 05-30-2009, 01:02 AM

luckie,
I know this is an old post, but I found it while trying to fix this exact problem in my house. Did you ever discover a solution?

luckie_reubs · 05-30-2009, 01:22 AM

I still haven't found a solution; sucking out the excess water with a hosepipe has been my solution so far! I'll keep you all posted with what I found out when I do find out something!