Plastic chips in sewer vent

Users who are viewing this thread

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
My vent was clogged with what looks like small plastic chips. I removed the equivalent of about a half gallon. After close examination, I thought that maybe the inside of the PVC pipe was deteriorating. However, where the stack goes through the roof, it looks fine. Anyone have any idea what this stuff could be?
 

Reach4

Well-Known Member
Messages
38,798
Reaction score
4,412
Points
113
Location
IL
How did you access those chips? Where were they?
 

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
I posted a picture of the bucket containing the chips. While investigating my clogged kitchen sink, I cut the vent pipe and discovered the plastic chips. They completely blocked the vent which was causing the drain to back up. After clearing out the chips, all is fine.
After thinking this over, I have come to the conclusion that a rodent chewed through the pipe. I plan to use a snake light/camera to check it out.
 

Attachments

  • VentChips.jpg
    VentChips.jpg
    92.3 KB · Views: 253

hj

Master Plumber
Messages
33,602
Reaction score
1,041
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
quote; I posted a picture of the bucket containing the chips. While investigating my clogged kitchen sink, I cut the vent pipe and discovered the plastic chips. They completely blocked the vent which was causing the drain to back up. After clearing out the chips, all is fine

If you cut the vent pipe because of a clogged sink drain, you made extra work for yourself, and a clogged vent, but itself does NOT prevent drainage, (in fact an unvented drain may often drain too fast), so you were wrong on both counts and probably still have the original problem, if you just cured the symptoms.
 

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
Okay, my description of what I did was incomplete. I also ran a hose into the drain (beyond the vent) and unclogged that pipe as well. Discovering the clogged vent was actually an accident. I cut the vent in order to have access to the drain pipe (I'd probably have to take a picture of this in order for it to make sense). I originally tried to flush the drain with a hose just below the kitchen sink (after removing the trap) and it backed up. Everything is unclogged now and the kitchen sink drains fine. My concern at this point is a chewed up vent some place between my roof and crawl space.
 

WorthFlorida

Clinical Trail on a Cancer Drug Started 1/31/24. ☹
Messages
5,727
Solutions
1
Reaction score
982
Points
113
Location
Orlando, Florida
... My concern at this point is a chewed up vent some place between my roof and crawl space.

If squirrels can get access to your roof check the lead sheathing (assuming you have lead) over the vent pipe. Squirrels love to chew on the lead and it may have keep chewing into the PVC. Squirrels are like beavers when it come to their front teeth; they need to keep them sharp and short. They do not eat the lead. I learned this when I climbed poles for New York Telephone many years ago. At one time all telephone cables (before WWII) were lead and when they were strung from pole to pole, the squirrels would chew a small hole through the lead into the paper insulated wires. Water would wet the insulation and it would cause shorts. It took a few decades to replace all lead cables with PVC insulated cables.
 

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
Mystery solved! The chips are ground up egg shells. The accumulation was due to a combination of grinding egg shells in the garbage disposal (which, in and of itself was not a problem) and the faulty drain/vent configuration. As can be seen in the DrainOld.jpg, there was a horizontal tee (the vent was connected at the right). The new configuration is shown in DrainNew.jpg. The drain is on the left and the vent is in the middle.
I immediately recognized that the horizontal tee was not legal, but I did not realize that it was actually causing the problem. Looking into the vent, it appeared as if the debris was coming from above. In hindsight, I now realize that the debris was pushed up the vent and then water from the roof made it appear as if it were coming from above.
Well, here is another example why the plumbing code is what it is.
 

Attachments

  • DrainOld.jpg
    DrainOld.jpg
    63.1 KB · Views: 267
  • DrainNew.jpg
    DrainNew.jpg
    41.8 KB · Views: 243

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
Okay, what's wrong with the second photo? Perhaps I provided a misleading description in the post with the photos. In the second photo, water is flowing from left to right. Not seen, but just at the left edge of that photo, there is a 90 elbow and a pipe coming down from the sink drain.
 
Last edited:

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
Never mind, I think I figured it out. Since the weir of the trap is higher than the connection to the vent, it is effectively the same as an S trap configuration which is not allowed.
I scanned in a picture from a Plumbing book produced by Time-Life. The middle illustration shows essentially the same setup as my kitchen sink. The orange is the drain and the green is the vent. So, would it be accurate to claim this book is wrong?
 

Attachments

  • TimeLifeIllustration.jpg
    TimeLifeIllustration.jpg
    77.6 KB · Views: 214
Last edited:

Reach4

Well-Known Member
Messages
38,798
Reaction score
4,412
Points
113
Location
IL
The middle illustration shows essentially the same setup as my kitchen sink. The orange is the drain and the green is the vent. So, would it be accurate to claim this book is wrong?

That left middle sink picture is very wrong. I am not at all expert on venting , but that one is very non-subtle.
 

Cacher_Chick

Test, Don't Guess!
Messages
5,458
Reaction score
213
Points
63
Location
Land of Cheese
A sanitary tee is only used to transition from a horizontal drain to a vertical one. No part of the fixture vent can be horizontal until it is at least 6" higher than the flood rim of the fixture.

IMG_20141211_180817.jpg
 

Mchiarit

New Member
Messages
27
Reaction score
0
Points
1
Location
South Carolina
Okay, so the tee for the vent connection should be a wye plus the location relative to the flood rim of the fixture is not allowed, is that correct?
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks