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Author:
sum (FL)
Sometimes when you try to solve a problem, as soon as it is solved a second problem shows up.
I had a previous thread where I was running into a overflowing washing machine stand pipe. The washing machine is located on the outside - against an exterior wall, in a "lean-to". When I run a load of laundry, during the drain and spin cycle, it will discharge at a high volume and overflows the stand pipe.
I then inserted a washing machine hose into the stand pipe, turned on water - no overflow.
I then inserted a garden hose into the stand pipe, turned on water - no overflow either.
There is either a partial blockage downstream, or the pipe underneath is undersized. My plan is to have it snaked.
So yesterday I replaced all the plumbing in that lean-to, new washing machine valves (the old ones were corroded and cannot fully close), new hoses, I cut the 2" PVC off and moved the P-trap to the far left, to make provisions for an 18" laundry tub.
I saw a 1.5" galvanized vent on the roof, located 4' inside the wall where the washing machine is. When I cut the PVC pipe at the wall, I was able to look into that drain arm, and see the connection to the vent 4' in. On the other side of the wall is the kitchen. I think this is how things are connected.
The 1.5" galvanized vent on the roof is inside the interior wall behind the range and refrigerator. The washing machine is on the other side of the wall to the right, it goes 4' to tie into that vent. The kitchen is on a penisula and the drain runs from the sink along the half wall, then makes a right to tie into the same vent. In other words, the kitchen sink drain and washing machine drain are connected to the same vent. Now on the roof the vent is galvanized 1.5", but it is possible the wet portion below is 2" CI.
Another test I did was to fill up the kitchen sink, then removed the stopper, the water drains fast, then slower, then slow, and about half way through it slowed down A LOT. When I had the washing machine drain cut at the wall, I was able to see with a flash light down the washing machine drain kitchen water flow past, confirming the kitchen drain ties in HIGHER then the washing machine.
So today I called a drain cleaning service, when he got here I explained everything. He went up the roof and snaked from that 1.5" vent. After some distance he said he felt a soft blockage, most likely a grease build up he said, he snaked another 20' beyond that, and retrieve the cable. I then filled the laundry sink and let it drain. No overflow! Problem solved!
After I paid the drain cleaning company and they left, I tried another load of washing and that did not overflow either. Now I haven't tried a load with detergent but I will later.
I went back into the kitchen and turned on the faucet, drain drain drain no problem.
I then repeat the other test, filled up the sink, removed the disposer stopper, and I noticed the same issue, it drains fast, then it slows slower slower slowest. Why? It will eventually drain in about 30 seconds, but why am I still having this issue? The clog has been cleared!
After some measurements here is a sketch of the top view. I showed the kitchen trap arm in red, and the washing machine trap arm in green. I measured the length of the kitchen trap arm and it's about 12 FEET LONG!
According to my calculations, if the trap arm is plumbed at 1/4" per foot, a run of 8' will seal off the top of a 2" pipe, resulting in an S-trap, a 12' no doubt. Is this the reason why the sink will drain with a faucet open, but with the sink filled up and the stopper suddenly pulled, it slows due to a vent issue?
Here are two pictures of what the connection looks like in the sink cabinet. I am not sure what I am seeing here. It looks like the tailpiece and p-trap is 1.25" tubular, and it has a series of adapter going from there to 1.5" to 2" SCH 40? Am I right?
If my assessment is correct, that the kitchen sink is draining slow when full is due to a vent issue caused by too long a run, can this issue be solved by adding a AAV under the sink cabinet right before it goes into the wall?
Sorry for being long winded, I think the other details are relevant.
Edited 1 times.
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Author:
KCRoto (MO)
Any 4" drain that you can access through a 1.5" line will never be cleaned properly. I doubt that even a mini-jetter would have the ability to get the job done effectively. You need to have access to the 4" line, and get the line cleaned with properly sized equipment. The guy that did the job through the vent needs to come back and do it right, and free of charge after access is in place. Cleaning drains from a roof vent is ALWAYS A BAD IDEA, and is seldom effective.
--Edit: Hj was correct, I misread your post. Cleaning the 2" through a 1.5" vent should be adequate, but unless they had you running the water full blast in the kitchen and washer while they did it, it may not be cleaned as well as it should be. If you can drain a full load from the washer at the same time as you drain a sink full of water, it would satisfy me.
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Author:
sum (FL)
KCRoto, I don't have access to the main line. The structure is 1955, and looking at the vent being galvanized, and there was another vent on the roof that is 4" CI, the underlying line is old CI. Everywhere else I look inside the property is PVC, and it was converted to city sewer in 2008 and that part is PVC. There is no full size access. There is a bathroom 20' downstream of it which if the toilet is pulled will have access, but it's downstream of it and no drain issues.
The only thing I could think of to provide access is to go to the outside CO - there is a PVC CO there but one way FORWARD, so I can't even see down it. I could excavate it and cut the line and replace with a two way CO or two one way, and use a jet to sweep backwards if necessary?
But I think the kitchen drain issue is not related because the laundry is draining fine now and at a high volume, and the clog was downstream of where the washing machine and kitchen drain meet. I am thinking the kitchen issue is either a trap arm that is way too long (in excess of 12') or something is also partially clogged inside the trap arm.
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Author:
packy (MA)
someone installed a new sewer line in 2008 and did not provide a full size cleanout?
maybe the used the excuse that it might freeze ...
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Author:
hj (AZ)
He said the main line was four FEET away, not that it WAS 4" pipe. The drain slows down as the pipe fills with water. The problem could be the fitting they used to connect the sink and washer at the riser. Some have severely restricted openings on the two branch connections. You may have too MUCH information in your post so it is difficult to assimilate it all. Maybe they should have snaked the sink's branch arm. What is that brown "circle" on the standpipe? NOT a cleanout, I hope.
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Author:
KCRoto (MO)
You are correct, I misread the "4'in" as 4 in.
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Author:
sum (FL)
Not a cleanout. The brown circle is a santee I glued in on top of the p trap in anticipation of a laundry tub. I should have put in a 2" test tee but didn't have one so I taped it with masking tape.
I agree the post has a lot of details. I will try and edit that down some.
But basically I think my question can be boiled down to two.
(1) will a 12' long trap arm, 2" PVC have trouble draining a kitchen sink filled with water at a steady speed? Or will it drain fast then slower...and no issue at all with faucet running?
(2) what is under the sink? Those are glued connections and can't be taken apart, is it 1.25" tubular to 1.5" sch40 to 2" sch40?
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Author:
KCRoto (MO)
The disposal is 1.5" tubular and it should have, but probably doesn't have a vent on that piece of counter. If the 2" was clean, the line should still have sufficient air flow in a 2 inch line with a 1.5 inch line draining into it. Once you have greasy water flowing through, that can change in a hurry.
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Author:
hj (AZ)
Run the sink until the water slows down, THEN either run the washer or look down the standpipe. IF the problem is in the common drain the water will be backed up, otherwise snake the sink drain TO the vent line.
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Author:
KCRoto (MO)
He just had the common line run from the roof down, and under the kitchen sink is all glued together.
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Author:
hj (AZ)
Then it has to be "unglued" and snaked.
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Author:
sum (FL)
where do I buy a can of the unglue?
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