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ruditeesen
Feb 18, 2008, 03:52 PM
Hi

Just moved to a new place, and lovin' it -- except for the kitchen sink.
It drains very slow, and backs up into both bowls.

I dismantled the whole construction, but no clogging in the PVC-pipes.
There was a Studor Redi-Vent installed, see STUDOR (R) inVENTive Technology (TM) - Air Admittance Valves (http://www.studor.com/redi-vent.htm). Without the Redi-vent, water drains fine and fast, but I can't quite have the water running.

Tought it might be the Studor, and got a Oatey Inline Vent (like this In Line Vent :: Oatey.com (http://www.oatey.com/Channel/Shared/ProductGroupDetail/278/In_Line_Vent.html), just not in Chrome. $3 at HomeDepot). The Oatey does not improve things.

Any ideas? Your help is much appreciated!
Regards, Rudi

massplumber2008
Feb 18, 2008, 04:03 PM
Hey ruditeesen... Does not sound like a vent issue at this time. I would suggest that you try this:

Plug up one side of sink with a rag... fill both sinks with water to about 3 inches... then have friend hold down rag while you plunge that drain... Here, the push will be more important than the pull ('cause of vent).

Try this for a minute or so.. see if that improves things. If not then time to clear that drain with a power snake.

Let us know how it goes. If my answer helped please RATE THIS ANSWER by clicking on rate this answer button. Thank you.

ballengerb1
Feb 18, 2008, 04:30 PM
Let me understand this, when you remove the AAV everything is OK, right? You replaced the AAV with an Oatey and the problem persisted but if you pull the Oatey it drains fine, right?

massplumber2008
Feb 18, 2008, 04:33 PM
Hey Ballenger... he said : "without vent water drains fine and fast, but I can't quite keep the water running". Why I went for the plunge or snake idea.

ballengerb1
Feb 18, 2008, 04:36 PM
Yep, I was bit confuesd by " but I can't quite have the water running." Maybe he can explain further

ruditeesen
Feb 18, 2008, 04:50 PM
Thanks for the quick answer.

To be more precise:
It's a double sink with a p trap and an inline vent about 6" above the trap. Then the pipe goes into the floor.

What I meant:
If the water runs at slow volume, it drains "ok" -- with or without vent. It backs up at higher volume, and if I had taken the vent off, the water is pushed into the cabinet.

Maybe the floor pipe is clogged?

Rudi

massplumber2008
Feb 18, 2008, 05:18 PM
YUP... drain is clogged. TRY my plunger trick.. then get back to us.

ballengerb1
Feb 19, 2008, 11:42 AM
Sorry but I got to ask another question. 1st you have the sink drains, 2nd they come together and then enter a single trap. 3rd the single trap then has an AAV mounted horizontally 4th the drain leaves the AAV does a 90 and goes straight down into the floor. Do I have your piping described correctly?

ruditeesen
Feb 19, 2008, 11:55 AM
Sorry about that. Once again. Please see below.

massplumber2008
Feb 19, 2008, 12:06 PM
Hey again... DID YOU TRY THE PLUNGER TRICK?

If you did and it did not work then I would remove that vent and snake the drain line... replace vent and test. Period. It is what I would do.

ruditeesen
Feb 19, 2008, 12:09 PM
I'll try the plunger trick -- but need to buy one first, my wife won't let me use the bathroom one ;)... I'll post if it worked, by tonight.

ballengerb1
Feb 19, 2008, 12:12 PM
You could also try temporarily capping the vent with a wet towel and then plunging. The AAV as installed makes regullar plunging out of the question since it vents the air rather than allowing the sucking action of plunging..

ruditeesen
Feb 20, 2008, 01:07 PM
Hi again.
Tried the plunger trick, and it definitely improved matters. I capped the AAV-pipe and the 2nd sink with the towel, and plunged the other.

Water drains faster, but still not perfect.

STRANGE: After letting the pipes run full with the AAV-pipe stuffed with a towel and plunging, the water drained very well -- so well, in fact, that I could not repeat (filling pipes, stuffing, plunging). However, as soon as the AAV was put back on -- and I tried either the Oatey or the supposedly better Redi-vent -- it drained again slower.

massplumber2008
Feb 20, 2008, 01:42 PM
Hmmm... well that is not totally out of ordinary... when vent not in... more air enters drain... so flows better. The AAV can only let in so much air to system and still keep sewer gasses from entering your home... so not a surprise.

Tell me... if you put the cap/plug back in and remove the vent.. how does it drain then? Then take advantage of totally plugged drain.. have a friend hold that rag in other sink... and fill sink and plunge again... let me know what you find.

If that does not do it... will probably need to snake the drain... but try all this and get back to me.

If my answers help, please RATE THIS ANSWER by clicking on rate this answer button at upper right or at bottom of this post! Thank you.

ballengerb1
Feb 20, 2008, 02:34 PM
OK now is the time to fill both sinks with the hotest water available and maybe an extra bucket or two of hot water. Pull both sink stops at the same time and allow to drain. If this doesn't cure you ills its time to rod. You may have trouble with a 1/2" rod but I'd try that first, you could drop down to a 1/4" rod if you have to.

ruditeesen
Feb 21, 2008, 12:27 PM
It's worth than ever now. Strange. It does in fact drain slower than ever.

What do you mean by "rod" -- snake the floor pipe?

I'll still try the baking soda/vinegar/salt-hot water trick.

ballengerb1
Feb 21, 2008, 02:30 PM
"baking soda/vinegar/salt-hot water trick" No, skip the water until the mix soaks over night. 1/2 cup table salt mixed with 1/2 cup baking soda then dump down the drain. Tomorrow flush with a bucket of hot water. Rod/snake are the same thing, remove as much of the black piping as you can and then rod down through the floor. Make sure the pipes you remove are also clear, probably will be.

massplumber2008
Feb 21, 2008, 03:52 PM
Hi Rudi... Hey... like Ballenger said... try the stuff he mentioned overnight... then here is what I would do.

Then, if not improved enough to make you happy... remove the pipes that you can by hand. Then go to store and rent a small electric snake... 3/8" cable size should be good...and machine should come with a set of leather gloves. While you are there, purchase an 1.5" ABS dandy clean out fitting (also called a test tee.. see pic. Below) and the proper cement/primer (read cans) and some teflon tape.

Now, go home and with a hacksaw or a sawzall cut out enough of the horizontal pipe to cement in the dandy clean out fitting (Please hold against yourself when cutting the pipe so do not break below the floor) Then, before cementing the cleanout on...snake that drain.

You could go down the vent fitting but will be much harder than if you just cut in a nice cleanout close up near the front... and that cleanout will be readily accessible for the future as well.

So then you snake the drain... go 25 feet or so... working back and forth/ back and forth... then cement dandy cleanout on, install remaining fittings, teflon the dandy cleanout plug and install that and then test your drain line.

Test by filling the sinks and draining... that should do it... if it does not undo dandy cleanout plug and go for it again... this time with a trickle of hot water as you go... try to churn/clear the pipes that way. Once you see her starting to clear, increase the water flow which will wash your snake and increase the washing/clearing of the drain line while working with the snake.

LET us know how it goes!!

ruditeesen
Feb 23, 2008, 03:09 PM
Just for the record here -- and I will make that clear in a rating later -- without your guidance I'd have had to call (possibly expensive) help already. Really appreciate it. I think as well that we're getting close to the problem.

See the pics below, all taken in the laundry basement below our kitchen --

Pic (1) On the right the vertical black PVC is the double kitchen sink floor pipe. On the left you can make out an older vertical metal pipe, which comes down from the bathroom NEXT TO THE KITCHEN. It looks as if they put the kitchen in at some point -- this is an old villa, split into 4 apartments -- and messed up the fix. Problem is that the PVC pipe that connects the kitchen to the bathroom and rest-of-the-house sewer drainage SLOPES DOWN TO THE RIGHT.

The bathroom sink drains perfect. All this points towards the clog being right in the L-turn from the vertical kitchen floor pipe, or?

Pic (2) is the "dirty fix", where they linked the kitchen drain to the older existing system.

Pic (3) is the left upward turn that kitchen water has to make, upwards.

Pic (4) is the head of that piece -- leading to my question: Can I just take that off, with a bucket underneath, scrub it out, and -- at least for now -- avoid re-doing the whole thing?

Rudi

massplumber2008
Feb 23, 2008, 04:40 PM
YUP... you sure can. Take a bucket, like you said and take that end clean out plug out. Most likely the problem is between the plug at end and the clamp on left (joining old pipe).

You will need a stick... swirl around... may even want to let some water drain out while holding bucket underneath and let the water backwash the pipe a bit.

Further, you can undo that clamp as well... slide clamp back, peel back one side of clamp and gently push whole pipe over just enough to get flashlight and see if there is also a problem there.

Otherwise, once you get plug off end...and use stick to get majority of gunk out...hook up a hose to hot water and wash the inside of the pipe down (you will get backwash here..so be prepared with bucket underneath). Slide hose in if you dare...cover pipe end with rag over hose..have someone turn on in spurts...that will wash down nicely.

AND as you said... you will need to fix that back pitch someday. I would just cut right above the fitting with the cleanout... cut out 2 inches or so and just clamp (Like other clamp) or cement on new ABS coupling... would not take very long... just be sure if doing form underneath that you check to not loosen anything upstairs.

Hey, just as you've been doing... keep us posted... on the downhill side now!

ballengerb1
Feb 24, 2008, 02:11 PM
It could be an illusion but is there any slope to that pipe between the clean out and the dirty fix? Doesn't look like any slope maybe even sloped backwards, can you get a level on it to check or eyeball it. MASS and I would love to be at your house with about 100' of pex, all that galvanized will cause you problems eventually.

massplumber2008
Feb 24, 2008, 03:19 PM
Your eyes are dead on Bob... that pipe backpitches awful... clearly why he is having the drain problem.

And you said it huh.. That galvanized pipe is going to be his next issue for sure... and Rudi...NOTE THAT HERE... when working on drain downstairs be darn careful not to hit the galvanized pipes... they will break/leak if mistreated.

ruditeesen
Feb 24, 2008, 07:04 PM
Allright. Stuff smells really bad.

We'll see how the old pipes hold up, tried to be careful.
The fix in between definitely slopes up towards the clamp, the T connection to the pipe from the bathroom is the highest point between the kitchen drain and the sewer.

It drains faster, but still not really well -- guess that's a physical impossibility, exactly because the water from the sink has to be pressed over that highest point.

Thanks for your guidance. Don't think I'll try to fix the fix myself -- landlord should do that.

Cheers.

PS Things I learned:
1 Try the plunger trick
2 Check the basement
3 Don't try to use an old clamp; they're only $5 at the hardware store
4... and be careful with mixing baking soda and vinegar... :)

ballengerb1
Feb 24, 2008, 09:34 PM
To change that slope cut the pipe 1" above the clean out and then see how much more is needed to be removed to give you a good ptch toward the drain stack, remove that much. Now just glue in a hub with a stop using ABS cement or all purpose cement.

alexanderleal
Jun 30, 2008, 09:57 AM
Hi.

I have the same problem.
I did the plunger trick but I noticed the more we plunged, the slower the drain goes. I haven't tried snaking it. I'd like to know if this is something I can fix our should I call a plumber.

Thanks.

Alex

massplumber2008
Jun 30, 2008, 03:08 PM
IHi ALEX:

F you can access the drain pipes... remove cleanout or remove the trap under the sink then there is no reason you can't rent a small electric snake from a local rental store and snake the drain line clear yourself!

You will need a hand-held electric snake (se pic.), leather gloves, and eye protection.

Be clear that if you snake the drain the snake can go UP the vent almost as much as it can go DOWN the drain... so have friend listen downstairs to confirm that you have in fact gone down with the cable. If you are lucky, the rental company will have a DROP HEAD attachment (see pic... bottom pic. Is a drop head!) that reduces the chance of snake going UP the vent!

First thing to do is to access the pipes under the sink...drop the PTRAP if possible and check the lines at the sink (clog could be up closer to sink then you think...maybe??).

Also, spend a little extra time reviewing this thread... lots here that may make it easier for you to have a successful outcome!

Let us know if you need more...

MARK

Milo Dolezal
Jun 30, 2008, 11:20 PM
Just one more detail: you have San-Tee installed as transition from vertical to horizontal. It is not allowed in my region by Plumbing Code. San-Tee is only used as transition fitting from horizontal to vertical. Replace it with Combination "Y". It will significantly improve your drainage.

massplumber2008
Jul 1, 2008, 04:16 AM
Hey Milo:

Just so you know... AND YOU START WATCHING FOR... ;) ALEX (post#25) popped in on RUDI's thread from February and posted his question here yesterday.

Rudi's all set... did you check the backpitch on that pipe back at his pictures though? No wonder why that pipe clogged!

Alex has yet to return.

Anyway, this happens quite a bit here. I am now in habit of checking the dates in the upper left corner.

Just wanted you to know... may save you a few minutes here and there!

Have good day Milo...

MARK

Milo Dolezal
Jul 1, 2008, 07:58 AM
MassPlumber2008: Yes, indeed, it is an old post. Anyway, I did check his slope. Just like you suggested, it appears to be back-sloped Also, it is 1 1/2" pipe. In my region, we have to install 2" pipe for kitchen sink drains. In my own house I've built last year, I installed 3" drains for both kitchen sink and washing machine. Now I can sleep better...

Btw: those crawl space photos of his plumbing are scary... They scream for plumber's attention... :-)

massplumber2008
Jul 1, 2008, 03:14 PM
You said it! Wonder how he made out overall.. Hoping he cut it like Bob suggested and is all set!

I also pipe 2" to kitchen sink with full size cleanout. I haven't had a clogged sink since I started doing that (about 5 years now).

Hey, word around here is that some code books are going to require 3" ptrap for residential washing machines ... coming pretty soon...

Have you heard anything about that in your area?

Let me know...

Thanks... MARK